I’ve made 3 “I Spy” donation quilts with fleece backing (no batting). I bound one - cut the binding 3” - worked well.
Other 2 after quilting, I cut the fleece 2” larger and turned it (2x) to the front. One backing had diagonal pattern (lines about 8-9” apart) so I merely stitched the lines - very happy with my diagonal quilting so I’ll be looking for fleece with a similar pattern In the future.