This tip provides an easy way to install cabinets that are level every time. It is especially helpful if you are hanging cabinets as a single installer. Purchase a laser level guide and set it up in the room so that it can show a laser line on all 4 walls. This will save a lot of time for measuring and marking the walls. Once you have defined the top line you can make a few marks with your pencil so that you know where to stop the cabinet.