Brenda, two things come to mind. Actually three. First and most important, make sure you have your table absolutely perpendicular to the blade. It must be. Second, make sure you have your blade tensioned correctly. Third, use a blade that will move the sawdust out of the kerf as quickly as possible. You don't need a reverse tooth blade. A skip tooth blade is probably best. And something a bit on the coarse side. I offer this because after cutting the 8 side panels on the piece I showed the other day, I learned all of the above. Keep at it, you'll figure it out.
One other thing, let the blade work. Don't push too hard or it will "bow" the blade and make sure you aren't pushing to either side.