Keep picking a run up the middle when you are on offense. Run a few yards and then press to dive forward and end the play. Try to rush 3 times per firrst down so you can get more rushes in per drive.
After each play, press to run a hurry up offense because you want to make sure the same running back is in the game the whole time. If you ever don't run a hurry up offense, the computer will substitute in the second string running back. If this ever does happen, just run a few plays with him and the starting running back will get substituted back in.