Don't let your nerves get the best of you. Stay calm and relaxed. Make sure to properly warm up so you don't gas early, I didn't see many people warming up at my tournament, I looked a little awkward warming up and staying warm between matches. I didn't have any problem staying gassed even with only 2 weeks notice coming off a 3 month break of doing nothing. Don't concentrate on getting a submission just get the points and if a submission appears before you then seize it. Snatch up the first points with the take-down don't sit their and be tied up in the clinch work on breaking the clinch for the initial take-down. Drill some clinch breakers a few days before the match and keep them in mind. Oh yeah almost forgot, watch the movie "Red Belt" repeatedly.