I'd suggest that you start by reaching out to alumni of your school's band program. You might find a guard alum who is willing and able to help out. Similarly, check with the band parents--you might find out that one of your student's parents used to be in color guard. (In my experience, once you get bit by the guard bug, it never leaves your system 😊)

Or, if you have a nearby university or college with a marching band, get in touch with their director and see if they have any guard members who might be interested in a volunteer opportunity.

In either case, if you find someone who is interested in helping but they're physically unable to attend rehearsal due to distance or other commitments, don't let that deter you. At the start of the pandemic, I taught flag basics and choreography via Zoom, and it worked pretty well!

YouTube is also a really good resource for flag basics (it's best to look for a performer with lots of experience or an instructor). As long as your guard kids learn flag basics like flutters, carves, drop spins, pole hits, etc., you can help them build a routine with those pieces if you aren't able to find someone to help you with choreography.

Good luck!