Stable-diffusion local speed improvement

I recently installed stable diffusion locally on my computer. It works great, but it’s not very fast (average of 1it/s), but I have a GTX 1080Ti with like 13GB of Vram, so it should work faster no ?
I tried to install xformers in the batch file (–xformers), it made no improvement…
I searched on this site and found many ways to improve the speed of the software, but I don’t know how to run the code lines.

For ex this optimization I don’t know where to put the code lines ! In a file, or running them in powershell ?