If you want to get the best player out of college with the first pick of the draft start a franchise with the trade deadline off and sim or play the game until week 17. Then look for the team with the worst record and trade your first pick for their first pick and for some reason they always accept letting you select a guaranteed NFL superstar in the next draft. This glitch also works for second through to the seventh round draft picks.
If you want to have a 99 right off of the bat just be a fullback and give him 90 blocking and bad 5 point things. Always make the higher points the higher percent of points. And a wide receiver has 99 kick/punt returns