Don't listen to what coaches say.
You'll constantly hear coaches make all sorts of claims about the upcoming season, players and games. Go by what they do, not what they say.
Don't listen to scouting reports.
You'll hear tons of reports about how xyz is looking fantastic in camp and is gonna challenge someone for the starting role. You'll hear about how players are gonna be given a second chance with a new offensive scheme/coaches/team/etc etc. If that guy previously sucked, he probably will continue to do so.
Don't believe the hype.
Every year proven performers get passed up for the next big thing. Many of those next big things turn out to be one-hit wonders. If you think two guys are equal, side with the proven vet. Justify to yourself in no uncertain terms why you think the rising star is better.
Stay away from strategies that advocate you never or always should do something unless they have very very very solid reasons for doing so. Even when you agree with the solid reasons, get second and third opinions from opposing viewpoints.
Stay on top of the rosters
Everyone takes this to a different degree. At least make sure a guy you're drafting to start for your team is listed as the starter on the depth chart. That may sound obvious but...
Here's a nice primer for draft day strategies. It's more general than specific, but that's where I like to start.
That's a good website btw, tons of good articles. The Cafe has some articles too I hear.