I actually think it's a bad idea to spend too much time reading what successful GMAT takers say. Chances are just as good that they'll give you bad advice or discourage you. (You know the whole thing about not letting your plumber be your pilot.)
Of course this is the place to find the people who are experts at the GMAT and at helping people get better at the GMAT but I'm just throwing my two cents in there.
Out of everything I've seen if you have big quant problems like me and need directed study, GMATQuantum is as good (and cheap) as there is--again just my two cents.
I think that just studying and doing questions is how you get better (it took me from a 560 to a 710 so far and I have a month left).
The people who are "naturals" are usually quant majors in college who have been fascinated with mathematics their entire lives so it's not surprising that they do so well after a short amount of study. (Those types usually just need a few weeks to exercise their under worked verbal muscles.)