How do I use Stable Diffusion?
In order to use stable diffusion you first have to have access to the model, this can be done either by running locally or by using online services.
The most popular way to run locally is by using AUTOMATIC1111 stable diffusion repository available here: https://github.com/AUTOMATIC1111/stable-diffusion-webui
after following installation steps you will have a website running locally that allows you to prompt directly to a stable diffusion model.

Note that in order to run stable diffusion locally you need a GPU with a high enough VRAM, 6GB should be enough.