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

I do mine at home also and never have a problem. The best trick I have found is four grease old linoleum square tiles. Grease the middle of two. Jack a tire up and slip it under the contact point of the tire with the concrete. Do the other side the same and jostle the bejesus out of it to get her to settle. She will slip and slide and come into harmony with the world. Attach my alignment tools, start measuring and make some adjustments.