How often, and how, do you clean your stylus?

I use a brush once a day. I have the Humminguru S-DUO, and a Hudson vibrating stylus cleaner (NOT ultrasonic even if sold as such). The S-DUO does work, but it is fiddly to use as you want to be sure not to get moisture inside a cartridge. Consequently I used it once and haven't used it again.

I used to use Stylast, but no more: it rusted out the armature from a Decca.

Just for the record (!) the S_DUO does have a shallow distilled water bath that the stylus is immersed in. It comes with several rubber washers to make the sidewall of the bath, so that the height of it can support the cartridge with just the stylus and cantilever tip getting wet. The stylus is not supposed to touch the bottom of the water bath. As I said, very fiddly to use. However it does work (I posted before and after photos here) and I do believe it is ultrasonic in nature.