How i can improve my skills in maths and in answering tricky questions?

I agree that practice is the most important thing. That being said, I would suggest taking the suggestion that there`s no creativity required with a grain of salt. For "tricky" questions there`s a certain amount of creativity often required in order to figure out how to answer the question. Some tips: 1) Try simple cases. If you`re asked to prove some property for all integers, first try plugging in the nubers by hand for the integers from one to ten. The idea is to sort of intuitively figure out why the answer should be true (if you`re supposed to prove some given result), or what form it might take (if you`re supposed to calculate something). Once you have an intuitive idea of what is going on, it`s then easier to figure out the rest of the details. 2) Practice tricky problems! They don`t have to involve advanced math, the idea is just to practice solving problems you haven`t seen before. There are loads of books out there of this sort of thing. If you are too lazy to buy / illegally download such a book, you can look up past problems from math contests, e.g. (in rough order of difficulty) uiversity of waterloo math contests, the MAA contests, putnam + IMO. If you`re interested in problems in some more "advanced" math such as advanced calculus/analysis, I would recommend the two calculus books by spivak which have some nice problems. 3) Really I have to emphasize that you should be doing problems you haven`t seen before, so that`s this one as well. 4) If you really want, there are books that are devoted to problem solving. e.g. "How to solve it" by polya and "problem solving through problems" by larson. 5) Seriously, do problems.