One absolutely critical skill for any kayaker to learn is the roll. The roll is how you stay in your kayak and get back upright if you capsize.
Rolling is tough to learn in the water for the same reason that bracing is difficult, and that is the natural fear that goes with capsizing. Because going over is scary, you tense up, and then you have a hard time getting the techniques down right. This only contributes to your fear of capsizing, since you are not good at recovering. Learning can actually get harder and harder.
One great way of intervening before this gets out of hand is to get out of the water. Leave your boat and paddle behind for a while. Just sit down on the ground in your kayaking position, and practice the techniques on dry land. There is no capsizing to worry about.
You can focus fully on the movements and posture and on getting everything right. You can teach your muscles how to behave without all that tension messing up your technique.
This video demonstrates how you can practice rolling techniques on dry land. You’ll learn how to position your hands and shoulders and how to rotate your hips and buttocks to get just the right movement.
After you start getting really comfortable with roll movements on dry land, ingraining them like they are second nature, you will be ready to start practicing with the boat and paddle again. The next time you go to practice a roll in the water, you will probably still get nervous, but all that training will click into gear.
It is far more likely you will do the right thing despite your tension. Since you’ll have taught your body those movements, you will instinctively call on the techniques you have learned on dry land even if you are panicking. This should result in a much more effective roll!