We talked a bit about female hygiene, today we shall talk about it in general. Keeping clean while in survival mode won't weight heavily on your mind, however I will reiterate that hygiene is an important skill to have when you are in emergency survival.
Soaking the inside bark of the tannic carrying trees, will produce a solution of natural insect repellent. The amount of water you add or subtract will determine that strength. This same solution can be used as a "soap" as well. Just remember that it doesn't lather up very well, and not only stain you a dark tan color if used too strong, but will stain your clothing as well. (like it will matter much in this situation)
You can also make a general cleaning antiseptic by crushing and seeping pine needles in water until the surface of the water is oily. for handfuls of pine needles will yield you about a thimble full of a powerful cleanser (you can use this at home as well, not just for survival)
Any plants that contain Saponin can be used to make soaps.