 First thing you're going to do is measure the length that you're wanting to cut and make a mark. Then you're going to take a square and you're going to make another mark at the other end. It doesn't have to be perfect. Then you're going to take masking tape and you're going to tape that line on the laminate side of the countertop. By taping the laminate side of the countertop with masking tape, this will eliminate splintering of the laminate when we saw. We will now turn the countertop upside down, measure once again, and we should be in line with this tape when we make our mark from the other side to cut. Pad your saw horses with rags or towels so you don't mess up the finish side of your countertop when you turn it upside down. With your countertop upside down in place for cutting, go ahead and measure where you want your mark, the length of the countertop from the very corner to where you're wanting to cut and make a mark. At that point, you will take a square and you will run a line straight across the nine degrees to the other side. Put that on the other side is where your masking tape was placed. Should be in line with this mark. I will now create a guide using a 2x4 so we can take the saw straight down that line for a smooth cut. Take your saw and lower the stage to where you have your blade resting perfectly center on the line that you created. Making sure that you are snug against this back wall. Now you will take a 2x4 and put it right against the saw for the edge and you will clamp this in place using C-clamps. Once the clamps are in place for your guide, check with a square to make sure it's a perfect 90 degrees. You will now take a smaller block and put it on the back splash using a square to make sure it is perfectly in line at a 90 degrees. You will clamp that small block down. You have now created a perfect guide to run your saw down to cut a straight and smooth line. When you do this, it is good to have somebody to hold the end of this so it doesn't snap off. Make sure you bring your stage back to where you are cutting deep. This will make a straighter line when you cut. Remove the masking tape and inspect the edge and it should be perfect. It looks good. I have checked for square. It is a perfect 90 degrees. There is any chipping on the edge and it is smooth and straight. Just what we want.