>>1155774Decide on the camping gear you need for when you're on land, then throw it all in a waterproof roll top backpack. (pic related)
In addition to the backpack and camping gear, Get an extra paddle, a water syringe in case you spring a leak, life jacket, whistle, and some marine rope to tie up your yak.
If you're the fishing type, bring a fishing kit, too.
IMO canoes are a little bit better suited for water camping, as they can accommodate more gear.
Make sure that your yak isn't weighted too low to the water's surface before you start your trip. Most yaks are rated for sub 300 lbs, and it's easy to load up on a lot of extra gear because you're not exactly hoofing it.
I've taken my kayak to a couple islands int he puget sound for some minimalist camping, and I've found I don't like the way my seating position feels with a large pack on my shoulders, and my storage compartment is not large enough to fit all of the gear I put in my pack.
TL:DR practice your set up before you set out, or you'll feel like a fool, and look like a fool if you're not going alone.