Set your laminate onto a sawhorse with the edge you wish to cut leaning slightly over the edge.
Measure the length of laminate you need to cut off and use a straightedge to draw a cut line down the length of the laminate.
Run a line of masking tape down the length of the cutting line so that you will be cutting alongside the outer edge of the tape. This will help prevent the saw blade from chipping the laminate.
Adjust your saw blade to be a bit lower than the thickest part of your laminate. If the laminate is already attached to a countertop or other piece of wood, leave about an extra quarter-inch for the blade to sink through.
Line your saw up about 1/8 inch from your cut line and bring the saw up to full speed before slowly cutting down the cut line.
Sand the 1/8 inch of excess laminate down with 200-grit sandpaper. Use an electric sander to speed up this process. The sanding will clear up any minor chipping from the sawing.