Homelab

I'm getting ready to run cat6 at my house. I know where I want the cable to go and its all going to ultimately come back into a closet in my office upstairs. What I need is some guidance on how to cut the hole in the ceiling of the closet, what size, and how to "dress it up" so to speak so that I can end up with something clean and somewhat "professional" looking instead of just an oddly shaped jagged hole in the ceiling with a bunch of cables, and probably insulation, coming down. What's the proper way to go about this? And any additional tips you want to throw in that might help me along this journey would be most appreciated. This will be my first time running cable in a home.