The individual pieces for the steps, and how each individual step was assembled. I had the lumber yard cut a 1x2 and a 1x4 into 6" pieces for me. The lumberyard that I went to did not charge me to do the cuts, but I do know that some places charge per cut. Ask first.

Once they were cut, I used screws (not nails, remember to predrill small holes to keep from splitting the wood) to hold them together. Over time, nails will work apart, so I don't recommend them for steps. You need eight steps to go up a cube's height.