Store it properly after each trip
The first thing you should do when you get back to shore is empty your Itiwit inflatable kayak. To do so, simply open the drain plug at the back of the kayak's hull and tip it up to empty out all the water that is in the bottom.
Once you have done this, deflate your kayak (the seats can remain in place), fold the two sides in on each another and roll it up, trying not to leave any fold lines.
At home, you will need to unroll it to rinse it with fresh water and leave it to dry before rolling it back up again.
The best way to dry it out completely is to remove the seats and then the floor and leave them to dry separately. Once everything is dry, put it all back in place and pack your kayak into its bag. This way, it can wait patiently for your next trip, even if that's in a year's time.