The corner where you are
The best writing, in my experience, comes out of direct experience of a place, a people, a time. These are things you know in your body, a somatic memory that allows your character to move in a developed, authentic setting. Grounding, some call this, and it’s a good analogy – like Anteus we take strength from touching our mother earth.
Sometimes people write best what they have left behind or lost. Nostalgia perhaps, but it can also be powerful.
So what makes a place/setting? Macrosetting is the larger place and time, including the historical and political milieu, artistic and religious presence, climate, architecture, scientific or technological advancement and ethical concerns. And microsetting is the immediate, intimate surround of the story – whether an Atlanta apartment or a West Virginia hill farm.
Specifics are the key – a mountain valley in the Smokies has its own biota, from trees to birds, as well as geographic underpinnings, the land-record of logging and farming and mining that can be found. A valley over, some things can differ – even more so from here to Virginia, to West Virginia, to the end of the Appalachians in western New York. In North Carolina's mountains a traveler might kick at a rock and see it glisten with mica and garnet – in Salamanca, NY, a trilobite might roll up. And of course if we transplant our characters to the Rockies or the Alps then we have a lot of ground to cover fictionally as well as physically.
Why be so specific? Because otherwise characters are in limbo – like the perceived place where unbaptized children go, neither hell nor heaven. It’s like being in a mall – it seems every one of them smells of Cinnabon and had a Spencer Gifts somewhere. It’s a kind of limbo, because once inside that cocoon you could be literally anywhere in the United States.
So – participate in the environment. Be sense-ate. Some things you immediately know or recognize. The smell of the slow waters of the Bog Garden near my home as opposed to pluff mud. The way mist nestles down into the valleys between the mountains, or lies like a comforter on lowland fields. The taste of iron-tinged spring water. The taste of livermush. The way a Carolina chickadee’s song is different from a northern Chickadee’s – and no it doesn’t sing bless your heart! Others you must dig down to get, the smallest of details.
You can’t fake these things. You can research some of them. Sometimes you goof - I was reminded my my errors by a reviewer who noted that I'd made my folks stoop to "top" tobacco when it would be tall - this was my humbling moment, as I'd noted the errors in other writers along the way.
I don’t think there is a substitute for being on the ground in the place you wish to write about, with any luck for a good chunk of your life. An impulse with younger writers to set stories in glamorous places and among glamorous people – not in their own perceived limited and dull experience. But the Bronte sisters constrained to a rural parsonage were able to use the moor’s reality to create powerful literature. “Brighten the corner where you are,” is a great saying as well as a book by Fred Chappell, who used his native place of Canton to range far and wide thematically.