I've never done one, so I can't give first hand knowledge of installation, but I can give my thoughts on it.
I looked into doing it myself on my '65 Barracuda and decided against it, mostly because of my bad neck. I have done carpets and seat covers, so I'm not unfamiliar with interior work and I did watch the guy install it as he came to my house.
First thing seems to be getting it centered. He marked the center of the car and the center of the headliner. From there it was a matter of getting it in the right places and stretching and gluing as needed along with a lot of patience. I had pulled the old headliner out along with the front and rear glass and took the seats out before he got there. When it was done, there were a couple small wrinkles, but he promised they would come out after it got parked in the sun once or twice. He was 100% correct with that. The headliner is just about perfect.
When I first talked to him, he told me the glass had to come out... Then when he got here, he seemed surprised I did it and then said it didn't need to be removed, but it did make it easier. I say this because it seems like most of the interior guys I've ever met have inhaled a little too much glue and are kind of "different".
Expect to pay at least $400 for installation, probably more.
If you are up for some fussy work that requires you to crouch and look up, go for it. There's some YouTube videos that will probably help. The worst you could do is screw up the headliner and have to buy another and have it installed, if you want to look at it that way.
Hope this helps, John