If you're looking to raise your benchtop, there are a few things you can do. First, make sure that your bench is level. You can do this by using a spirit level or a ruler. Once your bench is level, you can then start raising it by adding blocks underneath the legs. If you're not sure how high to raise it, start with a couple of inches and then go from there. You can also add weight to the top of the bench to help keep it in place.