Sand the entire countertop with medium-grit sandpaper to rough up the surface. This will help the laminate tiles stick to the countertop.
Clean the countertop thoroughly with mild cleanser. Rinse well and allow the countertop to dry completely.
Locate the center of the countertop and mark it with a plus (+) sign. This sign will be used to ensure that the first tile is applied squarely. The top edge of the first tile will be aligned with the crossbars of the plus sign. All other tiles will be aligned with the first tile, so square placement is essential.
Remove the paper backing from a laminate tile, and apply it to the countertop, placing the upper left corner of the tile squarely on the crossbars of the lower right quadrant of the plus sign. Roll over the entire tile with a rolling pin to ensure even application and to encourage adhesion.
Remove the paper backing from another laminate tile and apply it to the countertop, aligning with the first tile. Roll over this tile with the rolling pin. Continue applying tiles and rolling with the rolling pin, using existing tiles as alignment guides. In spots where full-size tiles will not fit, cut the tiles with sharp scissors or a utility knife to desired size and shape and then apply.