Pinokio 1-Click installation for SD.Next: Advanced Implementation of Stable Diffusion (https://github.com/vladmandic/automatic)
You should be able to install either the SDXL version or the SD 1.5 version and it will grab the appropriate model files and whatnot for you.
IMPORTANT! Currently only the Diffusers backend works with SDXL, so you will need to switch the "Stable Diffusion Backend" option inside Settings/Stable Diffusion in the webui from Original to Diffusers to get it to work.