1. I stuck short pieces of skewers into a hole I wanted to patch until they fit snugly, and then I put an elastic around that bunch. Don't let them fall in if you are working with a sealed pontoon!
2. I mixed Marine Epoxy with sawdust.
3. I covered the skewers with the mix and put them back in the hole, filling all the gaps with epoxy/sawdust.
4. After it dried I used an angle grinder to carefully (CAREFULLY, and angle grinder will EAT YOUR BOAT if yo let it :D) flatten the surface of the boat.
5. I took pictures because the ends of the bamboo look cool :).
6. I covered the flattened patch with more epoxy and/or resin paint.
7. After _that_ dried we went sailing! (The person in the last picture is not me)