You should teach yourself to play as minimalistic as possible. And to fight temptation. This is the biggest difference between tournament players and casual players. Tournament players usually don’t hit too many buttons, or panic. They generally focus on trying to find things instead of trying to force things. Of course I don’t know what type of player you are, but since you only have two times to lose before you’re out, focus on the following things:
Just work on baiting, walking, and whiffing safe pokes. That way you get a feel of what type of opponent you are up against. The is the biggest thing. If your opponent likes to jump, there is normally a reason. This means he usually doesn’t have good ground. Typically taking the ground way from these people is good.
Notice what moves your opponent love to stick out where you are close, and notice if they mash out moves when they are under pressure. This means they are nervous, and they will start to throw out attacks. Know your matchups, your frames, and your counters.
Does the person keep attacking? People who like to attack a lot will usually do really unsafe stuff to stay on the offense. Why do they not want to be on defense? Do they have issues blocking low, blocking overheads, teching throws, or escaping mixups? Learn to exploit these weaknesses.
If someone turtles, trying to predict what they are going for. If they love to stay at ranges and stick out certain pokes or jump back in the corner learn to bait them. The best thing you can do is to chip them and wait. They are looking for a good opportunity to hit you, if you can successfully bait this, they will start to question their gameplan.
And the biggest thing is be patient. Patience is the biggest difference between loser bracket and winners bracket.
My strategy is to play really defensively, block everything and look for throw techs. I start to see if my opponent is getting frustrated, and then that’s when I start to pull out the stops. At the end of vanilla, I played a Blanka player in a local tournament. It wasn’t a huge one. The first game I purposely played really defensively, not sticking out many moves, so I can see what he was up to. I noticed his attack patterns and shut down his Blanka in the subsequent games. I was able to take his air game from him, and block his crossups. I also notice he didn’t incorporate throws into his mixup, and I took advantage of that by blocking his attacks and counter poking him when I knew I was at the right distance. That way I was able to completely shutdown his Blanka. Remember, in tournaments, it’s more than just a battle of characters, or a battle of knowlege. It’s a battle of strategy and minds. So try to be unique in your approach so your strategy isn’t easy to figure out.
Good luck with your first tournament, and you have the support of the SRK Guile family.