Step 1: Parts
I made them so the stool fits perfectly under the table. Each wood part is drilled at its extremities. Use these holes to create a jig that will help you for rounding the corners with the lapidary. Cut some square parts the size of your long parts. Drill them in the middle. They will serve as spacers between the ''stairs''. Once you've got all the parts assembled as showen in the picture below, cut the extra rods and tighten with nuts. (if you are on summer time, the wood will tend to get slightly shrink when winter comes, so keep a free access to the bottom nuts.