The one problem that I had with this project is that I live in eastern Idaho and it's late December.
Apologies if some pieces of this don't make as much sense, this is the first one of these I've done from a mobile device and I tend toward ADD.
Step 1: Gather Materials
4 3" bolts with washers and nuts
8 4" hurricane straps
About 80 1" screws (I had a bunch of small drywall screws lying around from an previous project)
4'x8' sheet of Hardboard (optional)
Liquid nails or some other adhesive (if you use the hardboard)
I tried to find 4 identical pallets at local businesses without success. I finally gave up and bought four #1 pallets from a local refurbisher. The pallets cost a total of $28.
Everything else I picked up at Home Depot and a local hardware store.
Step 2: Prep The Pallets
I cut the top boards off of 2 pallets and the bottom boards off of the other 2. I started with a circular saw but some of the ends of the boards didn't want to stay on the pallet. So we had to pull the nails and boards off. This is not easy. Pallets are made to stay together.