I have a single F horn, and no matter how many videos I watch, I can't get the procedure demonstrated in videos to clear moisture from my horn--but all of the demonstrations are on a double horn, which I imagine changes things a bit. What is your go-to move for clearing moisture from your single F horn?

Pulling the tuning slide, rolling the horn around and getting the water out the bell, and in desperation, pull the individual valve slides and dump.

Thanks, didn't realize I had to roll the bell around with the tuning slide out, I just kind of turn it over, but that makes total sense to me now. Does it matter what direction I turn it? Do I hold valves down?

A single horn should be pretty easy to clear. The steps I would suggest:
- Remove the mouthpiece
- holding the horn with the bell to your right, leadpipe opening up (like the horn is in your lap while resting), remove the tuning slide.
- Rotate the horn 1/4 turn, press the valves for a second to get water from the slides.
- Continue to rotate the horn until water comes from the leadpipe and the main slide tubes.
- If you still hear water, rotate the horn so the valve slides face down, then remove each slide and rotate it until you are sure it is empty.

I play a double, and sometimes the water gets a long way in. I tend to have a bigger puddle at the end of rehearsal... Just remember, it is not "spit" , but condensation. I guess I just have more hot, wet air than most!

Good Luck!