First, your environment. That becomes a biological given. It produces the beings you're writing about. Culture is how biology responds and makes its living conditions better. I have a background in archaeology, and as well sayanthropology as well, since the two disciplines share certain principles.

And I know biology. This helps. If you haven't got that background, look up a similar critter, study it, understand it. Did you know that camels don't store water in their humps?

If you're investigating a terrestrial culture, you ask yourself certain questions, all the while realizing it may show very great differences from the way your own culture does business.

First set of questions: "Where do they live? In what? How is it built? Is it inward-looking or squared with others, is it round, are the dwelling patterns in relation to each other, and what relation?

As an example of something different from the USA, in ancient Catal Huyuk, people built like a hive, passing through one another's rooms on their way to their own. In Cnossos, a temple-center defined the heart of organization, along with its stores and supplies. Modern cities can be built like a wheel, like Rome, which expanded from an ancient city, or like Oklahoma City, which was laid out on two grids with a jog in the middle---the story goes that two surveyors missed each other, and traffic forever jogged over a dangerous ten feet right in the heart of town until they built the Convention Center atop the point and solved the problem.

Tents, houses, caves?

And are the rooms in the houses square, or on the square, or might the houses be round, and set in a ring? There are cultures that don't necessarily grasp the idea of a straight line. If people live in a world of natural shapes and curves, a straight line is a fairly alien thing and even the value of straightness may not be understood.

How rooms relate to one another says something about the social organization. American houses have one big common room and individual bedrooms all in a line, with separate baths, if possible, and the kitchen attached to the common room. Some cultures think cooking smells are disgusting, and want the kitchen completely away from living areas. Some cultures have the whole family in one bedroom, or the common room is the bedroom, and individuals feel lonely and scared if asked to sleep alone.

There are round houses, square houses, houses with separate wings, houses with an 'upstairs' for the family and a 'downstairs' for the staff. There are cultures where parents build adjacent houses for their children as they marry, until the whole thing becomes an interlaced complex of housing, with women sharing kitchen chores and men going off to work in adjacent fields or businesses.

Second set of questions: "What do they eat?" and just as important, "How do they eat?" in all sorts of senses. On the ground? At tables? In automobiles?

In Pakistani culture, food preparation is lengthy, complicated, and extremely social. It takes up a significant part of the day and involves a lot of social interaction among the women. The advent of fast food can change this, but if it does, it will change everything, culturally. Culture shock and cultural destruction can come from things which to us seem a triviality.

In the US, fifty years ago, a family ate at the table togetherand young ones didn't leave until everyone was finished, no matter the tantrums. Kids learned to sit still.

In many US households now someone, male or female, comes in with fast food meticulously wrapped in environmentally unfriendly containers and it stands on the kitchen counter to be grazed-upon at will until it turns disgusting...after which it is not fed to the pigs, which would raise more pigs, but tossed into a city landfill at great effort of trucks with robot arms. That's a change within, say, 75 years.

Cooking styles. There's burying it in the ground under coals. Or using a microwave oven. There is from-scratch cooking, which starts every mealtime with flour, salt, raw vegetables. There is yanking a fish from the river, running a stick into it, and plopping it down over a fire. There is social eating, around a campfire or a fancy restaurant table, for very diverse reasons. There is religious fasting, and religious feasting.

Food can be a major or a minor part of the day. Some cultures have lengthy social nibbling around a common pot, while an American may wolf down burgers in huge gulps while driving and balancing a cell phone. That says a lot about culture.

Next questions: "How do they pass on knowledge?"

Direct observation, perhaps, one hunter to in, "Don'tstand in front of the mammoth."

There is formal schooling, with an instructor under astreetside awning---or in a fancy classroom.

There is apprenticeship, and guilds, andguild standards which dictate who can enter what profession.

There is religious instruction, and secular. 

There is a style of instruction that emphasizes repetition of tradition, by rote, and there is instruction that encourages question and challenge. There is instruction that lasts a few years, satisfied when the child knows what the adult family member does; and instruction that goes on for decades under the tutelage of paid experts, that leads to a piece of paper and the pronouncement that the student is now an expert.

More questions. "How do they bury their dead?" and "What do they think happens to them?"

Societies that believe in rebirth may bury their dead in jars, in foetal position; societies that need space or venerate fire may cremate...societies have exposed their dead to vultures, then tenderly gathered the bones. Societies have buried the deceased under the earthen floor of their houses, to keep them close. Societies have mummified and built elaborate tombs. Or bundled them in cloth and put them in cliffs or on mountaintops.  Some have even eaten their deceased relatives, or enemies, out of respect.

Ask: "Is every death the same? Do they sacrifice members of the group?"

Bog mummies were probably leaders killed asvoluntary sacrifice, then thrown into peat bogs, to please the gods.

Which didn't get you points for the hereafter in all cultures. Suicides couldn't be buried in sacred ground in mediaeval Europe. And that was somehow supposed to affect whether you got to heaven or not.

Ask: "Do they think their dead go to an underworld like their present life, or filled with strange creatures, or do they think they live in the clouds or get reborn, or will there be a Twilight of the Gods or a Fall of Saturn when the whole world changes, and even the gods go down?"

Is there a good afterlife and a place of torment? Do they think personality continues, or is the deceased absorbed into the World Soul, the compendium ofall life?

How much of personal resource do they use preparing for their funerals? Do they visit the dead, and do the dead visit them?

In ancient Rome, tombs were set on roadsides, and had inscriptions to salute the traveler and tell them about the life of the deceased. Greeks and Romans both believed in ghosts and actually liked the notion of their ancestors coming back to visit. The Romans kept death masks of their ancestors, and repeated personal names endlessly, unless someone disgrace one of the names. Then their mask was not kept, and the tarnished name was never used again by the family. Marcus was never again used by the Brutus family.

Certain cultures treasure mementoes of the dead. Certain others fearfully get rid of all possessions of the dead, dreading them coming back and imaginingthem as jealous or angry.  The Greeks would not retain a memento of the dead.  The Egyptians believed a body had a ka, a soul that went to paradise fields to serve the gods, and a ba, a birdlike soul that hung about and sometimes visited relatives. They also believed that if your name continued to be written or spoken somewhere or if an image of you existed, your soul would live. When those all went, you were gone.

There are traditions about undead, and uneasy dead. There are rituals, even staking down through the rib cage, to make the dead stay put.

The Romans gave their dead a coin for the ferryman, and put it in the mouth of the deceased, being unsure if the dead had pockets...practical folk, they were. But they wanted to be sure you had your fare.

On to self-concept and universe-view. "How do they define their universe?" And: "How do they define themselves?"

The Romans saw the earth's surface as fairly unending, and spoke of the 'circle of lands', meaning the Mediterranean, which was as much as early Romansneeded to know. Later generations have reinterpreted this as the globe, but early Romans didn't know the earth was round.

Greeks said the ocean was strange 'beyond the pillars of Hercules', the two boundary-posts the hero set up. The pillars of Hercules seemed to move, incidentally, being early on pretty close to Greece, and later being the Straits of Gibraltar.

Very educated Romans, however, knew an old Greek had measured the circumference of the Earth (pretty accurately, too, and also calculated the tilt of the Earth's axis, in 276 BC) but the knowledge got lost after the fall of Rome---since the philosopher that said did the math said other things the Church didn't like. It took a later age and Christopher Columbus to prove the old Greek was right---in 1492, which proves how long bad information can proliferate. I have personally met people who still think the earth is flat, because their preacher told them so.

As for self, and identity, this is by no means an easy question. The Romans had serial names, alternating on a three-generation cycle, but not too rigidly, and actually didn't have much in the way of personal names, only clan and family names. You were one Caius in a three-hundred-year cycle of Caiuses and Luciuses, you were Julius because Julia was your clan (and your sister's name, and your daughter's, etc., etc. forever) and you were Caesar because all this side of the Julian clan had that surname. So you had one quasi-personal name and two family names, and if you were female you got a nickname to keep you distinct from all others. Men often didn't get a nickname: they were just one Caius in a long, long succession, and were responsible for the name: foul it, and it would never be carried again. So who are you? More 'we' than 'I,' mentally.

Culture affects your psychology in ways that aren't covered in modern elementary educational psychology.

In the 1700's-1800's in western culture philosophers began to argue about common individuals having rights, even personhood, as distinct from kings and lords, and while the common man didn't quite grasp the philosophical nuances, he sure liked the idea that he had a right to what the aristocrats had, hence a period of revolutions. "I" became all-important. In the 20th century, "nationalism" began to be the thing----we common folk of Nation X are better than Nation Y.

And how many pieces does consciousness have? As above, the old Egyptians thought of self as tripartite, with your physical body, your 'ba' and your 'ka.' Preserve the physical body and the two other parts could carry on in a world a lot like this one, except the gods were much more present.

As for the Egyptian concept of the world at large...the world was the Nile and various lands they knew, and if you got beyond that, there was desert and scorpions. Ahmose (common as the name John) the Egyptian hoped to have a nice life, afford a nice burial for himself and his wife, and to be revered by his descendants with a lot of offerings. His ba could fly about at night, his ka would live forever, and everything should be truly great if he could just get his life in order and be buried with potent charms. Ahmose hoped the priests who had the job of praying constantly would keep the gods connected to the world and in good health, so that the world would continue to work well, and the floods would continue to come. It seemed as if the gods were kind of sleepy, uncoordinated powers that had to be kept awake and on the job, the world not being high on their priorities. That was, of course, why Egypt had a Pharoah, a sort of god-delegate, to take a personal interest and keep the other gods focussed. As Ahmose saw things, it was worth showing up on the labor details and working, because the Pharoah, due to his job, had a solid grip on eternity, and if he even mentioned you in his tomb or represented token workers that sort of represented you among ten thousand others, you were 'in' for all time.

In sum, not many cultures actively wondered what was beyond the world they saw, and not every culture saw 'I' as that important, since 'I' couldn't survive very well. 'We', in the form of family or clan, was much more likely to survive, in certain cultures' way of thinking, and had a demonstrable continuance through time, on a personally available level.

So the evolution of 'I' is a curious thing. 'We' seems to be justas popular in human history.

And what's beyond the end of the world? Why should the worldhave a shape, or be anything but endless hills or endless water?

Philosophers worried about that sort of thing. Until they write books and until ordinary folk could read, it wasn't so likely to come up too often in conversation.

Nowadays we worry about the shape of the universe itself, whether it's closed or open---but bring this topic up at your local bar during a football game, and see whether modern society has really advanced too much beyond the old Romans.