First off, are you rich? If you're not. Have fun paying back HUGE student loans.
Secondly, take and ace the SATs. Don't know what they are? You really haven't given this much thought.
Thirdly, check out that site.
Also, don't think you're going to get into MIT. Know you're not, that way you'll only be pleasantly surprised instead of absolutely crushed. Look at other universities and decide if you really want to go overseas and pay exobitant fees.
(To give you perspective, I'm originally from the states but decided to become a citizen here to get into uni here. HECS FTW).