I do a bit of worldbuilding for the sake of it, so hopefully this might help.
Firstly, r/worldbuilding and r/conlangs can be very useful, in terms of resources, advice, and simply idea generation.
That being said, you can go at it however you want. If you’re planning on writing a story, you might want to focus on what you intend to show and go out from there; if you’re more interested in the worldbuilding, you might want to start wherever interests you.
Constructed languages (conlangs) can be useful in helping name stuff, but in my opinion, aren’t entirely necessary to construct a world. If you smash enough consonants and vowels together you might end up noticing certain sounds that a “culture” favours. From there, you end up thinking that a certain element of a word means something and so on. r/conlangs as I mentioned above can be useful if you’re looking towards developing a proper language, but it’s not my thing personally.
There is always the possibility of grabbing elements from IRL cultures too. Many settlements are named pretty simply, denoting their purpose. e.g. places with “ford”, “burg”, “gard”, “ton” in their names. However, not all have to follow this strict method, as they can be named something else by a particularly arrogant founder, be adopted by a foreign conqueror and corrupted, or simply contracted over time into something easier to say.
When it comes to cultures, you could work based on what you’ve got.
If you’ve got a map, for instance, you can use geography to dictate culture:
- Areas with large, fertile land will probably see agrarian cultures spring up, along with cities, and probably some sort of stratified society.
- More barren, open areas might favour pastoral or nomadic societies, where trust and ability is emphasised.
Alternatively, you can work back from a concrete concept and use that to round out a culture. For instance, if you have a culture that favours infantry warfare, you could draw the following conclusions:
- It has little or no stocks of horse → It must therefore import them from elsewhere.
- It has poor terrain for grazing horses→ It lives in a mountainous or hilly region.
- It has a cultural bias against cavalry→ It has developed a reputation for anti-cavalry warfare.
Of course, you can draw alternate or multiple conclusions, but it can be a good starting point - or potentially a way to distinguish cultures that at face value might seem very similar.
However, you can just straight-up pick-and-choose elements from real life, and insert it straight, adjust it or use it for inspiration. I don’t get bored with “generic European medieval fantasy”, but others might. You could always just merge two existing cultures, or take a twist on an existing theme.
- Do you want the popular concept of feudalism put on its head? Look at bastard feudalism in the late middle ages, or the Scandinavian conflict between the fralse and bonde (where feudalism never really took hold), or the pronoia system in the Byzantine Empire.
- Do you want an empire known for its infrastructure that isn’t the Romans? Look at the Incas, perhaps.
- What does your culture value? How is wealth seen? The Aztecs, I’m led to believe, did not care nearly as much for gold as the Spanish did, while if you look at the Bantu cultures the wealth of a man is often measured in the size of his cattle herd.
- You don’t have to grab “past” civilisations for inspiration either, even if it is set in a pre-modern context. In Japan, sake is often served to overflow, but that’s a modern tradition (I’m led to believe). However, it wouldn’t look out of place in a similarly hospitality-focused culture in fiction.
Finally, you can just find some random inspiration in your everyday life. I’ve started one off purely from listening to Amorphis and Gloryhammer, and I’m sure plenty of other people have had weird ideas come from nowhere. Oh, and have fun: if it starts getting a drag, you can always work on something else, and inspiration can strike at any time.