have a tendency to play safe.
You'd be surprised at how many times "better" players end up at the bottom of the list because their "great drive" ended up OB and cost them a stroke. Or their OB caused a mental meltdown and a +2 hole...
From my experience, and those i talk to, it's always funny how the guys who end up at the top always say "i played it safe, everyone else tried the super hard lines and kept hitting trees or went ob... but i marched down the fairway and took my 3 everytime."
be conscious of the little things - you'd be surprised at how a little bit of wind, rain, wet discs, etc can affect an entire tournament (and some people's entire game).
Eliminate simple mistakes, things you can avoid, and play conservative, you'll be surprised that you will rank in the top 1/2 just by doing these simple things.