I don't know where is my fault and why I cannot do better in Codeforces. In Summary:

I have solved 339 problems 269 A, 60 B and 9 C

188 from dif 800, 40 from dif 900, 51 from dif 1000, 27 from dif 1100, 20 from dif 1200, 9 from dif 1300

I have solved almost 95% of a2OJ <1299 ladder. Now what should be my approach to do better?

I have read many blogs on google and codeforces, but can't understand which idea will work for me. I need your help guys.