Post-draft Tips for NFL fantasy league players

I just signed up for another league and I like the think I do a decent job drafting, but by week 7 or so it all falls apart as I seem to get outsmarted by other players with bench substitutions, free agent pickups and other acquisitions. Usually I start out with a winning record, then the wheels fall off sometimes from week 7-10.

Can any FFB players give me at least a few hints or rules of thumb as to how to do better as the season moves on?
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