1. ^^^ This but don't let the towels get cold or the bot eggs will "reattach" themselves.
The purpose of using warm/wet is to trick the eggs into thinking the horse (or another horse during mutual grooming) is licking them, and they release so they can get on the horse's tongue.
If there's no hot water at the barn, carry a hot thermos with you.
I prefer a bot knife to scrape them off and try to grow some semblance of fingernails to pull the ones in sensitive areas like the flanks. When the bot knives get too dull to scrape off bot eggs, they come in handy for scraping off manure (or caked on mud) before I start brushing.
2. Pull the hair back along the jowel and closely inspect for bot eggs. These eggs are laid by Throat Bots and self-migrate into the mouth.
http://www.equimaxhorse.com/parasites/bots/
Where it says in part:
I have a hard time staying bent over with my neck craned upward (this is what I get for teaching my horses to keep their heads in a down position when I'm doing something to that head), plus my fingernails leave a lot to be desired so I slather them in a thick layer of any kind of ointment. Vaseline, A&D, hemorrhoid ointment, anything to stop their movement and kill them.
They should easily come off by the end of the day or the next day.