I'm participating for the 5th (or 6th?) year in a row. I've never won but I'm hoping that this year will be it for me because I'm not studying so nothing else is demanding my attention and making me not want to look at a screen or write. I also have a way better plan than I have previous years so that is positive too.
To prepare I am looking at what has tripped me up in previous years and looking for advice on how to counter those things. Also just getting general writing advice. There's a really good podcast called Writing Excuses that has really helped me do my prep.