If you see your teammates play good D on a defender's jumpshot, start running down the court. Hopefully they'll get the rebound, and if you're open enough, the will always throw a perfect full court pass for an easy dunk.
I played 5 min quarters in the Summer League and scored 40 points off dunks only.
Currently Playing: NBA 2K11 and Halo Reach GT: Dchen40
Find one or two good things about your player and ride them until you can spend points to make him better all around. You don't have to be the primary scoring option, especially as a PG. If you don't see a lot of shots going down, or unable to get yourself open, work the floor as an assists machine. An A teammate rating is good whether you score or not. Also, find one drill you can do all the time for 400 points (silver, gold with a bonus). For my SG, that was shooting as long as it worked mainly in the mid-range area. For PG, it is usually dribbling course if you can do the isomotion moves.
Once you are awesome at passing/defense/being fast, start putting points into shooting and slowly become an all-around player.