(One Punch Man fans will get the reference. Nonetheless the advice is still very applicable

)
You'll need to study really hard. The most important thing is sticking to the studying regime, no matter how it hard it takes. It took me 3 years to do this well...
Study 1 hour Chemistry
Study 1 hour Physics
Study 1 hour Maths
And then read 10 pages of other books
EVERY SINGLE DAY!
Of course make sure you eat 3 healthy meals a day, a banana in the morning is fine. Most importantly, make sure you cut out distractions and always works towards your ambition to strengthen your mind.
In the beginning you'll wish you were dead, you'll start thinking what's the harm in taking a day off.
But for me, in order to do really well, even when I'm so confused and frustrated till I pulled my hair out, I kept studying.
Even when I can't get the right chemical reactions, I kept doing Chemistry. Even when I can't figure out how to solve an equation, I kept doing Maths.
A year and a half later I noticed a difference... I became a nerd, but I became smarter! In other words, you gotta study like hell until you become a nerd to do really well.
The guys messing with "quick study tricks" and "memorizing formulas" will never get this far.
We humans are smart because we have the ability to change ourselves!