I'm about to try lucid dreaming. Any tips?

I'm about to try lucid dreaming. I'm going to take a nap. I read lots of tutorials and I think I know what I'm doing. But since it's my first time, some tips would be nice. Just random little tips will do. Like how to keep relaxed once it starts (if it starts). Oh, and how long (aprox.) does it take for the relaxation phase to p? That would be helpful to :) Thanks in advance! Wish me luck! :)