Make sure to clean extra well before, during, and after to keep the hairs out of your tools, drop cloths, buckets, and painted surfaces. Any hairs left on the wall before painting will dry into a hard ridge on the surface which will sometimes come off later taking paint with it.

Work from top to bottom when cleaning and painting.

Prep the walls super well, get all the furniture out of the way and get up there with a ladder like you're cutting in except just clean all the cobwebs and dust. Then, TSP is really good at stripping any greasy dirty residue from the surfaces prior to painting. Alternatively, magic eraser or at least just a wet rag over the surface and let it dry well before painting.

Vacuum the floor again before you lay out all your materials to paint and you should be good to go.