Put in a few drops of dishwashing liquid into a spray bottle filled with water. The more soap, the more time you have to position the decal, but not too much ! Spray that soap water onto the surface you are applying to. Peel off the backing of the decal. Place the decal on the soapy surface and position it exactly how you want it. Use a sheet of silicone rubber and squezee the soap water in the outward direction. If the soap water dries off before you can get things right, just carefully lift off the decal and respray. Try with scraps first until you get a feel for it.