As with everything you learn in life, you need to have a genuine interest into the matter. Once you really want to learn something, you'll start gathering information, can't stop thinking about it and swear an oath to yourself that someday, somehow you will succeed! KSP doesn't come naturally, at least to me it didn't. I'm no math genius and certainly no Einstein, yet I was able to learn the very basics of this game. Why? By reading these forums and wiki, by watching tutorials and documentaries... it took me over a month to understand what I was doing; even the simplest of things like reading the nav ball were obscured by shroud of mystery. All it takes is patience, a long attention span and the genuine will to tackle this game... as by magic there will come a point where you say: now I understand! And after that, new problems emerge 'cause the more you know, the more you start paying attention to, the more failures you get. If you like that, KSP is for you... if you don't, you probably give up pretty soon.