These are quick and super easy.
Cut out some fabric that is about the same size as the magnet. (Fabric stretches, so whatever you cut out will never stay the same size after you stretch it while using Mod Podge.) Apply a layer of Mod Podge to the front of your magnet and lay your fabric scrap on top.
Allow to let dry and then trim any loose threads, if any. (***You can always add buttons, ribbons, or any other embellishments to really sass these up. Go on, try it.)
Slap onto the fridge, magnet board, or wherever.