I am actually pretty slow as well, but I always try to use my time wisely. With Valentines Day right around the corner, I have already stocked up on supplies and am premaking as much items as I can and preparing for some craft fairs which will help local business in person :) Even if I don't make a sale, that is still getting my name out there when things are slow.
Use this time to build up inventory, edit photos, edit listings and policies to make sure everything is up to date. Taking the time to post on social medias about what your up to or new designs is always great!