I need steps that are light to pick up. The wooden steps are very heavy (60 LBS). The steps are 2' x 2'x 3' and 2 x 2 x 4. I want to make them from foam that is rugged enough to stand on and not crunch. I have never worked with foam before. Is there a way to cut it so it can be all uniform in size? What type of adhesive would I use? What type of foam should I use? Anything else I should know? Thanks