Help for January

Since Random Genre Month doesn't have a forum, I figured I'd post this here.
So I am thinking about doing Mystery for my novel this January for RGM but the problem is I have never written a mystery novel before. Now, I'm not 100% sure, it's between mystery and adventure, but it looks like it may be this.
So any tips for a newcomer that is writing his first mystery novel in a month?

Here's a reference: Plotting The Mystery Novel. It was posted on one of the other threads.

http://ticket2write.tripod.com/mysplot.html