Lots of things needed when you go for kayaking. It depends on you and where you want to kayak. If you go for fishing you need fishing types accessory but if you go for tour or adventures you need that types of thing. Considering these things, I will select some materials that you need. They are those :
Dry Bags and Dry Box ,Bilge Pump or Sponge ,Lightweight Tent ,Synthetic Sleeping Bag,Life Jacket,Water Filter or Iodine Tablets,Sunscreen,Watch,Paddle float,Compass (that floats),Towline,Maps and charts in waterproof case,Lip balm (SPF 15+),Insect repellent (as needed),Water in bottles or reservoirs-shielding hat,GPS (loaded with map files,Emergency flares or strobe,Two-way radios (1 in lead, 1 in sweep boat).
To know more about kayak you may visit here
Best Inflatable Kayaks in 2018 List of The Top Selling Models