I'm a forester and work in swamps. I can't use deet because it tends to give me the shakes (I use it when absolutely desperate). I just wear regular clothes underneath coveralls (Wahls etc) treated with Permanone aka Permethrin aka Repel(tm). One can will treat 2 pairs of coveralls and will generally last until the next laundrying unless you get soak. If you take a iron-on patch you can seal shut the access holes to your inside pockets. The twill of most coveralls is dense enough mosquitos can't easily bite through it.
The hitch is you must treat the clothing and let it sit over night before it's ready... you can't just put it on in the morning. Do NOT put it directly on your skin. It's safe once it's bonded to the clothing, but wet it's still an issue (This is the same insecticide that they use to treat lice or scavies BTW)
This works for mosquitos, ticks, and chiggers (if you tuck your pant legs into your socks. On top of that I wear a boonie cap and a army-surplus mosquito net. A pair of leather gloves and you're all set.
That's my rig... and I've used it in the most hellish mosquito-ridden areas I think you can imagine.
