I usually go for once a week to once every two weeks. But I do have a heated towel dryer, and k think that helps to keep bacteria to grow in them. My advice is to make sure you hang your towl somewhere they can air out well
I can suggest simply looking around YouTube. That way you can get a sense of how they work and what kind you'd like to know more about.
I happen to have practical experience with the, because I used to work on trains that had some giant versions
I have a fascination with VFDs/VVVFs/frequency inverters.
They are the controllers that gives of a specific hum/whine from electric trains/cars and from other 3 phase electric motors.
I'm making my own sudo-vvvf at home.
I just think they sound awesome and are Hella cool
I usually go for once a week to once every two weeks. But I do have a heated towel dryer, and k think that helps to keep bacteria to grow in them. My advice is to make sure you hang your towl somewhere they can air out well