When it comes to decorating the tree, I'm the light man. I program the outlet timer so that the lights will be on most of the time that it's dark outside except for when we're sleeping. I then put a string or two of lights up on the inside of the tree before putting four strands (we need at least another strand) of lights down around the outer edge of the tree. This process, which I've done since I was in high school (I believe I learned it from my Uncle Brian), gives the tree more depth and makes the lights look more like a starfield.
I largely stay out of the process of putting up ornaments. It might seem a little childish, but I haven't enjoyed putting up ornaments since my wife forbade me from putting up my Micromachines Star Wars spaceships on the tree. She thinks it looks tacky; I think that it's nothing short of awesome. Anyway, since I'm not allowed to decorate the tree the way I want to ... well, like I said, a little childish.