This diving board is made from a 42" x 22" Bodyboard.
An important feature that I wanted was an adjustable line retaining system. One of the main requirements for this was a strong hole through the front of the board for the float line to run through. After cutting the hole I had to figure out a way to reinforce it it so the line won't cut into the soft body of the board. I used a short section of PVC pipe of the same diameter as the hole. I also got the end caps for it, and then cut them into rings. I shaped the rings to fit the profile of the board and glued them to the PVC tube on either side of the board using PVC cement.
For the spool I used a frame made from PVC pipes and T joints. It's anchored in the board in the same manner.
For the adjustable line retaining system I used a cleat from West Marine. The cleat is held in place with two bolts going through the board and washers on the other side.
The flag holder is a piece of automotive hose with an inner diameter of perfect size for the flag pole, the pole stays in there with suction alone. The hose is glued into the board with Aquaseal and is solid.
A 15" x 30" bungee net, secured to the board with zip ties, is used to keep fish and other things on the board. A small but important detail was to use a dremmel to grind down the little stubs of zip ties that were left over after snipping them off. They were kind of sharp and can catch on the wetsuit as I'd be handling fish and shoving them under the bungee netting.
The first two pics are with the first line spool I put together.
I replaced the first line spool with this one made of PVC. Also serves as a nice handle for the board.