We started taking both our kids to USF games when they were infants (son is now 18 and daughter is 14)
If you can get club access seats, do it (just do not be surprised if your wife and child spend the entire game in the A/C)
Be patient, more than likely, you will need to leave early and you may miss most of the game play
Make sure that you have some sort of ear protection (either ear plugs or headphones) as well as some sort of cooling device (hand held fan, etc)
Participate in the things that appeal to young children (Rocky's Rookies Pre-Game Run, seeing the band before the game, waiving pom poms, spelling out SOUTH FLORIDA as part of the fight song) and do not be surprised if your child could care less about the actual play on the field