if you are tailgating, get there at 9AM (will save you tons of traffic headaches)
if not, i'd still get there by 10:30 (the traffic will be bad by then; it takes a while to park).
i start walking into the stadium 1 hour before kickoff (it takes that long to go through security, grab a beer, and get to your seat)
i tailgate... if i could make tomorrow's game, id be in line at the gate at 8:45AM (gates officially open at 9, but they always let people in before)
if you are in the 300-level, be prepared for lots of wind
oh yeah, MAKE LOTS OF NOISE