We put up lights ourselves, only around the edge of the first level, because we are not climbing on the roof. We use these Command hooks, which stay up all year since they are clear. And really last, we only up losing one or two a year that need to be replaced.
Big box store lights, on a timer to run from 5 p.m. to midnight. Projector on the garage, inflatables on the lawn. Tree and inflatable penguin on the front porch. Giant ornaments hanging from the twin dwarf palms. It just makes me so happy to see, I love it so much more than having professionals come and do a sterile outline of the house.
The other people may have better suggestions for hooks, but I have been putting up the small 3m command hooks, but when I was looking for a link, I saw these: light hanger clips from 3m command which I'm going to pick up a pack of for this year's christmas lights and see how they work.
I have pre-existing random nails/screws all over the place from the previous home owner but I've been moving to the hooks when I need something new. I think they look cleaner and less obtrusive than random nails.
I guess one thing to note is that I don't take the hooks down every year. I use it for halloween decorations and christmas lights, then just leave them up all year.