This is just some advice I've accumulated from my experience with cp thus far:

(1) Stop worrying about rating. If you're like me, perhaps you care about rating and contest performance a lot and take individual losses quite harshly. In fact, you may even act them into existence by worrying or anticipating that you will underperform in real contests. I have this experience where, even though I perform quite well during practice on my own and virtual contests and I know I'm able to solve hard problems, I choke when it comes to the real contest. This is usually due to the pressure I put on myself to redeem myself for recent losses and/or making a big deal out of taking a little too much time on a single problem in a contest.

(2) Actively push when you are solving problems. Just because you may not intuitively come up with a solution to a problem upon reading it does not mean you can not solve it. You have to push yourself to the point of feeling unnatural -- conjecture, guess and prove or disprove, make observations, do not be afraid of spending time understanding various examples, etc.

(3) Strong emotions never help -- both positive and negative. Of course, it is pleasurable to solve a hard problem after a good while of thinking and struggle, but the positives are just as intense as the negatives. If you allow yourself to attach your self-worth to your contest success, you will feel quite miserable. This is not to suggest not caring about contest performance -- by all means, keep practicing and trying to improve, but stop taking particular contest failures and failed attempts to solve problems so personally. Be as objective about the process as possible. Don't chalk up every success as being personally driven and allow every failure to seem like an incredible injustice done against you.