When is a Car "Level" - Home Front End Alignment

Buy a water level at a home store, easy to use to get (shim) 4 level spots for the cars tires to sit on. You can't really compare suspension angles to printed specs unless the car is sitting on a leveled spot. With my car nose into my garage, It was level side to side, but I had to put rear tires on some plywood squares to be level front to back. Once you find these spots mark them so you can return to them each time you check or make an adjustment.