How to set it up on various OS and GPU:
Ey. The state of Stable Diffusion in mid 2023 is: go nVidia (Turing RTX or newer), or go home. Because of Tensor cores and FP16, such a setup is about 5x, or 10x faster than previous-gen nVidia cards & any current AMD stuff.
RTX2060 / RTX3060 is best bang for your bucks these days. If you are loaded, go RTX4090, Quadro A6000, huh...
Windows or Linux, whatever works for ya.
As for installing SD, native install works. So does docker:
You must be registered to see the links
Regarding UI, go with Automatic1111 & see if you fancy some of its plugins (the plugins tab in the UI, gitHub, search fo em). Don't go overboard with em plugins, though - Python dependencies can get nasty, the whole thing can fall apart.
Civitai is a good place to download modes, per that GoodBad person above. And I'm the Ugly.
Any luck with yer image generation so far?