@sand
It's a real problem...I'm a hiker and gardener. For my face and body, I use Off! Botanicals most of the time. For worst cases, I use a 20% Picaridin formula like Sawyer or Cutter Backwoods (Deet).
If you are just sitting (on a deck, for example), a fan blowing will do the trick because bugs can't beat a 2-mph breeze.