The first rule of world-building is available physics, which basically means that if you want it to feel real, it has to follow the same rules as this world, from gravity to how human behaviour works. If you have a fantasy element that doesnt obey the laws of physics, make sure that it has a fantasy explanation.

If your appearance is all people see, they have no respect for your mind.

There's always a bit of truth in each rumour, the trouble is finding out which bit. - Tayend

The first rule of world-building is available physics, which basically means that if you want it to feel real, it has to follow the same rules as this world, from gravity to how human behaviour works. If you have a fantasy element that doesnt obey the laws of physics, make sure that it has a fantasy explanation.

How am I going to make friends with these people if all I can think of is how easy it would be to rob them?

I still recommend reading travel guides as an insight to a travellers perspective on fantasy worlds. Nearly all characters end up travelling at some point, and they have many of the same needs and concerns covered in travel guides.

Tayend nodded. “I know it won’t. I admit I was worried about you, but you are still your old self, underneath.” Dannyl straightened in protest. “Underneath what?” The Elyne stood up, waving one hand in Dannyl’s direction. “All…that.” “I’m reeling at your descriptive clarity,” Dannyl told him.