In a word, dont. As long as the countertop is solidly in place you can lay new laminate over the top. You need to sand the old surface to give it some tooth. Then use contact adhesive on both the old countertop and underside of new material let dry until slightly tacky, then use some dowels or other spacers to position new piece.Pull out spacers one at a time, smoothing as you go, then finish with a J-roller, trim edges and enjoy. Hope this helps.