Do - Draft a Running Back Very, Very High.
The running back position is extremely lacking in depth this year. After the first seven or eight there is a sharp drop, which is followed by another equally sharp drop around number 15. Simply put, if you don't pick up a running back in the first three rounds you are going to be living off of waiver-wire running backs, and that's not a very luxurious way to live. For those of you in two running back leagues, this advice is even more imperative - please pick a running back early.
Don't - Draft a Quarterback High (Unless His Name is Peyton Manning).
In my eight team league, Tony Romo, Matt Ryan, and Jay Cutler are all still on waivers following the draft. With that much depth at the quarterback position, there is no reason for you to be reaching for Russell Wilson with your third pick when you can pick up a statistically similar quarterback, Colin Kaepernick, with one of your last picks. Obviously, if you find yourself at the end of the first round, Peyton Manning might be an alright pick, considering he will be by far the best fantasy quarterback this year, but outside of him there is no need to go quarterback early. Be patient.
Do - Proceed With Caution When Drafting a Tight End.
There is absolutely no denying that the tight end position has top end talent, but there are questions about how much of that talent there is. Jimmy Graham should be a first round pick, which makes sense, Julius Thomas will probably go in the third or fourth, and Vernon Davis and Rob Gronkowski will probably be off the board by the fifth round. After that, unless you find Jason Witten or Jordan Cameron oddly dropping to the tenth or eleventh rounds, I would recommend passing on those 12 or 13 rounders including the likes of Martellus Bennett, Greg Olsen, and Dennis Pitta. Instead, wait until you can pick up a guy like Zach Ertz or Jordan Reed in the 15th or 16th. The best case scenario would be to draft a tight end high, but if that's not possible, don't panic and reach on a mid-level tight end.
Don't - Go on Autodraft.
This is certainly the case every year, but it is even more so this year. Seeing as ESPN doesn't update their player rankings to keep up with injuries and suspensions, you may end up drafting Josh Gordon, Le'Veon Bell, Ray Rice, and Sam Bradford if you're unlucky enough. Outside of the obvious desire to avoid players who are going to miss significant portions of time, your team is just going to be better if you're the one drafting it. For example, I'd much rather have Peyton Manning over Eddie Lacy, but ESPN's fantasy rankings have Lacy ranked higher - bummer.
Do - Pick For Value Over Need.
Most leagues nowadays have at least three flex spots per team, so, even if you feel like you need to fill up that running back slot, if there aren't any top-tier backs available, snatch up that star wide receiver who managed to slide down the board a bit. Flex spots are just as important as other spots and should be treated that way when drafting. Additionally, trades will allow you to acquire players in positions of need after the draft and the additional talent that you managed to nab will help you in your bargaining.
Don't - Pick a Defense Before Eighth or Ninth Round (Not Even the Seahawks).
Defenses are a fairly hard thing to predict considering how many variables they have, so why would you waste one of your first few picks on something so questionable. A large part of what makes a defense perform well or not is the opposition - searching the waiver wire for defenses who are coming up against dismal offenses (the Jets and Jaguars were great for this last year) will often yield you pretty solid results, and you may even end up finding a defense that you end up keeping for the rest of the year (see: last year's Chief's defense).