I mentioned in an earlier step that this is probably not the project with which you'll want to learn vinyl application. The skill of applying vinyl comes in handy for a range of art-related and fabrication-related tasks, and by itself is not altogether that complicated -- it's just sticking a sticker on something, after all -- it's a skill that you can
absolutely pick up quickly... but I'd start slower and build up to something like this. The three surfaces (esp. the ceiling), small fault-tolerances in mating the edges, and the cramped quarters make an expensive mistake very likely for the first-timer.
I hope I haven't scared you off from trying it sometime, though... The moderate difficulty in laying vinyl under the constraints imposed by this project is the exception, not the rule. If you're interested, there are
Instructables that cover vinyl install.
Here's one, for instance.