You can also roll the face edge of the foam back under itself gluing the face edge down to the board. Cut the foam larger than the board then leave the thickness of the foam around the edge of the board unglued. Glue the board in the center of the oversized foam. Then when dry glue the edges down, rolled under. This gives more support on the edge and no shape cutting is required for a perfect even curve. Also some cloth covering over the foam before the canvas or vinyl helps with support, wear and tear. Use opposite directional stretching when tacking the materials to the back of the board for an even cover, and remembering contact adhesive to both surfaces to be glued, allowing time for them to be touch dry. Once they touch eachother, it will not need to be held in place, instantly sticking.