Lately I've been using AI to generate character portraits since I'm terrible at art. This actually came in really handy for PaizoCon, since everything was on VTTs. Here are a couple of ones that I've gotten that were good enough to keep. They're definitely not perfect, but you can upload them back into Nightcafe and have the AI keep working on them later
Hokgnath Bladegnawer (Battle Oracle/Mindsmith)
Matu'uk Bladegnawer (Giant Barbarian)
Jerhyn Skorn (Throwing Magus/Rogue)
Here's the guide that got me started on Stable Diffusion:
https://www.youtube.com/watch?v=DHaL56P6f5M "Stable diffusion tutorial. ULTIMATE guide" from Sebastian Kamph (because that link didn't give a preview, just search for that on youtube to be sure you get a safe link).
The first 30 seconds of the video sounds like one of those weird text to speech readers, but then the guy comes in and goes step by step talking through installing and using the tool. You've got to install things like git and python and he goes through all of that also in detailed steps. Honestly it was one of the best "how to install python" guides also... ;)
Reddit's down now, but there were some great guides there on using prompts and using tools that customize models, train the tools, and more.