The surface preparation for applying an epoxy product to coat Formica starts out by removing any and all surface contamination from the surface. All waxes, oils, grease, dirt, dust, water, or any other liquids must be removed from the surface. Do not use any cleaners that can leave a film, wax, or polish behind. Then the surface of the formica must be abraded to haze the surface, at a minimum. Formica has a hard, shiny surface that is designed to repel stains and prevent things from sticking to it.
The epoxy relies on having a strong mechanical bond, and will have a difficult time sticking to shiny, smooth Formica, so the more coarse that the surface can be abraded, the better. After abrading, remove any sanding residue and clean the surface again, ideally with denatured alcohol or a high alcohol content isopropyl alcohol, then allow the surface to dry completely prior to applying any epoxy.