Don't do your fantasy draft until after week 3 of the preseason. Star players do tend to get hurt and you don't want to be stuck with a player that tears an ACL and is done for the season. In the meanwhile be patient, do your homework, and look for the unknown players that may be starting for the 1st time. You have rookies and players that are on the rise that will be overlooked by inexperienced fantasy players. I remember when Arian Foster and Miles Austin came out of nowhere to be huge fantasy players. Last year Fred Jackson of the Buffalo Bills was quiet and productive. At the quarterbacks spot you usually have to have a big name to have a good team. There are usually one or two rookie QBs that will have better than normal years so don't be afraid to take them in the 5th - 7th round. In my last year draft Cam Newton was smiling at me in the next to final round. It will be a long year if you end up with a bad QB.
Enjoy the preseason and I hope that you find a diamond in the rough! If you have some diamond in a rought players in mind please feel free to comment and share.