Recently someone asked me a question on Quora about how groups can help in competitive programming and I was reminded of I_love_Hoang_Yen's modelling of competitive programming as an obstacle jumping game and I went ahead to write this answer. I'd also like to share the text here.

There is a great post by I_love_Hoang_Yen where he tries to model competitive programming as an obstacle jumping game. I'd like to use same analogy here to help you. I have used some excerpts from his post, which I've italicized.

The 'science' of problem solving
For each problem, in order to solve it, you must jump over a gap or an obstacle. It can be either a difficult implementation, or some hard-to-see observation, difficult algorithm, etc.

For me, some problems are very easy (e.g. Codeforces div 2 A, B..), because those gaps seem so small to me, and passing through them feel just like casual walking.

Some problems are very hard. The gap is just too huge, or there are many many gaps, and you can get stuck in the middle because you're too tired after maybe first gap.

Or maybe there is some trick/concept that you don't know yet! Here you are, applying brute force or greedy technique to a DP problem; of course, you won't succeed.

But now comes your experienced friend, who has been doing competitive programming for a few months, knows how to do complexity analysis, so she knows brute force won't succeed, with some more convincing she proves to you why greedy is wrong and this is where working in groups is helpful.
Now, you'll easily cross the obstacle with some guidance.

If you have read Thanh Trung Nguyen's post you'll know what to do to improve yourself individually. You just need to keep learning new tricks and concepts, at the same time you need to make sure you aren't making same mistakes again. Occasionally, when are stuck, you can ask your friends for help.

Where to find these friends
You are looking for people who are doing competitive programming and a good community where people help each other to make the game more interesting; what can be a bigger community than Codeforces! If you are facing some difficulties you can always put up a blog post asking for help.
However, as I've noticed, some people might find online collaboration a little ineffective when compared with physical presence. Some abstractions might be difficult to understand when they are just written down, instead of someone explaining to you in front of you on a board or paper. If you are school or college student, best way is to look around you, you'll find plenty of people doing these contests and willing to discuss and share their knowledge with you. If there aren't any such people, you can form a programming club in your institution and inspire other people too to join you.

Good luck!

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