Rob, I make neck gaiters (warmers) for the homeless at Christmas. I can get 5 from a 2/3 yard piece of fleece. This is the pattern I follow.
https://uberpest.com/2006/10/make-your-own-neck-gaiter/
I cut WOF, then subcut into three pieces. Two at 23-1/2" and one at 13". The last piece is combined with another end piece so that gaiter will have two seams. (I hope that makes sense.)
They are quick to make up and always appreciated by folks who work or play outdoors.
ETA: If you have already cut up the horse fabric for mittens, you could make the gaiters from a solid fleece to coordinate with the beanies.