In daily fantasy sports games there are two areas key to winning long term.
The first of these are the rules of the game. While this seems rather obvious, knowing the rules of the game is key to picking a competitive roster. Knowing how many roster spots, cap or no cap, autopick draft order, etc... is very critical information.
Scoring is also part of the rules. How much for a complete game? Does plus/minus matter to my score? What is the difference between 1st and 5th place finishes in a race (assuming equal laps led)?
You need to know how on the field performance reflects your scoring total. IMO, studying the scoring table can be even more valuable than studying player rankings online.
While knowledge of rules helps you build a consistently competitive roster, it is strategy that helps you defeat opponents (especially good opponents) over the long run.
There is no "manual" for daily fantasy strategy and I'll be damned if I'm going to give away all of mine. But here are some scenarios think about:
-When to hedge and not to hedge.
-Why would you draft your 12th choice 3rd overall in an autopick contest.
-When it is better to sign up 1st or 2nd for a HU contest.
-When contests with higher rake have way more +EV than the contests with the smallest rake.
-When to take a risk on a "game time decision".
I could probably sit here and come up with another dozen scenarios, but I have stuff to do.
I just think a lot of my opponents don't pay enough attention to either rules or strategy. I can tell you this - the ones that don't pay attention to both don't last very long.