If you are noticed by a female, try your best to ignore her presence until you're dressed again. Use them only if absolutely no other option is available. In the woods, far from civilization, restrooms typically aren't available. Get behind sufficient growth that you are completely invisible to the remainder of your party, before you begin. Check carefully that you aren't near any sort of animal or insect den.
Ants are especially bad.
If you forgot toilet paper, bring a leaf identifying guide. Poison oak makes a poor substitute. Based on an unoriginal email forwarded by Dave Willens, December 1995.