Store your boat away from direct sunlight, all plastics deteriorate with age when exposed to ultraviolet rays. Store your boat either standing or hanging. Place upside down, on one edge or on one end. To hang, place boat on its side, held by straps. Do not hang by the handles or run straps through the holes as this may distort the shape of the hull over time. Hanging straps should be located on both sides of the cockpit rim where the plastic is the stiffest.   See the picture below:

My kayak is stored in my garage.  I constructed the hanging mechanism with materials on hand.  I used 2 bicycle hanging hooks and 2 old dog leashes!!!  The total cost was less than $2.00.  The following picture shows the hooks: 

On a final note, I needed to store my kayak accessories.  What better place than the kayak itself?

If you take the time to store your kayak properly, you and your kayak will have many happy years together.