BAMF adhesive products require minimal to no prep to use. Before applying the stickercals and/or vinyl to your surface, you need to ensure it is a clean, smooth and unsanded surface. If you sand prior to applying, there is a chance you will see the sanding marks even if you apply epoxy over the products that have transparent portions. Otherwise, you do not need to seal it, print it, use water to apply it, have long wait times before epoxy/sealing, etc. You can apply crystalac or epoxy immediately after application.