a few things
- Get a lot of VC. play proam, mypark, mycareer games and get high grades and good stats etc. Early on, don't spend VC on like clothes, just on upgrading your player or on moves that will help you get badges or do better to get more VC.
- Once you get to 88 ovr, start doing the practices on offdays to unlock more attribute slots until you get to 99.