Go to tractor supply and buy the 19.99 dollar sized bottle. Its called Gordons Permethrin 10 spray for livestock. Its one quart. Has measurements on bottle. I mix 1oz to a 20oz spray bottle. It says to discard that mix after 24hrs. I noticed after 24hrs it smells different like its rotten kinda. But if you dont mix it....it stays good so only mix what you need.

I spray everything. My clothes and face. I been using it for 5 years. Works great