Download either of those two generators. They'll actually do most of the walking you through it, and the "NO, you can't do that" stuff is built in. (As a side note, RED[/b] Is the bad color)
Once you have it kinda figured out, make yourself a character. Histories are just like before, only now instead of decks and cell phones, everyone carries "Comms," which does everything from turning your car alarm off to muting the TV so it's not distracting while you make out with someone, and also carries your personal information and everything.
Hackers (no longer deckers in 4th edition), have or program routines to screw with other people's comms.
In addition to comms, the matris is now wireless, and so anyone who has cyberwear programmed to recieve matrix feeds can see the "AR World" where reality is augmented by Matrix Billboards, signs, and the credit ratings of the people around you.
So download and try those character generators. Neither one prints on anything resembling a decent character sheet, but once you have your 400 points spent, you can just figure out how to type it into some sort of format on here, and we'll get started.
-kv