When you've mastered the torso and knee motion that rights the boat, you're ready to practice the roll. The essence of the C to C roll is the same motion. The curvature of the torso from one side of the kayak to the other rights the kayak from upside down. It is helpful to have a swim mask and nose plugs for this part of the learning process.
Note: a few of these rolling images may take up to a minute to load, in order to bring you high quality instruction.
The set-up position
This is a protected forward tucked position, with the paddle held on the water along one side the boat. From the set-up, you’ll flip, and wait until your boat settles upside down.
To start a roll, first get in the protected forward tucked position, called the set-up. Tuck tight. Place your paddle with the blade face up, and the shaft parallel to the left seam line. Your forearm will be on the side of the boat.
Hold the paddle delicately! If you hold it tight, this transfers stress into the rest of your body,and makes you more likely to "muscle" the roll. And muscling the roll is harder than using fluid technique!

Tip over
Once you are upside down, you move the working blade in an arc near the surface. Keep the blade near the surface by leaving the tuck position, and rolling your torso and working blade out to the side.
Your torso has to lead the arm motion. Any roll you do will rely on positioning the paddle with your torso more than your arms. Open up your body and arch your back to roll your torso out to the side. This gets you really wound up in the "first C".
Ideally, you have an instructor who can tap the boat when you are ready for the next step. The most common mistake is trying to take shortcuts, and not positioning the paddle correctly.
Knee Lift, right the boat

Then relax the knee that pulled you into the wind-up and rotate the boat up with your hip snap. Concentrate on minimizing the force on the blade.
As you start this motion, minimize the force on the blade and bring the boat up with your hip snap. Pulling down on the paddle and lifting your head to breathe are the most common ailments of rolls and braces. You have to believe! If your head goes up for air, the boat stays upside down!
Somehow this is a hard concept for us to remember underwater. Again: minimize the forceyou put on the blade. Instead of pulling the paddle down, think of sliding the boat under your upper body.
Finish position
Finish your roll in a safe position! To avoid injury, keep the paddle shaft low and in front of your shoulders. Use smooth finesse rather than power.
C to C Review, mental checklist
Take it to the river
Once you have a roll, practice it hundreds of times on flat water. Don't rush. Decide deliberately to stay in your boat unless you know of specific hazard. Wait until you can feel cool air on your hands in the set-up position.
Go methodically through the rolling motion. On flat water you can practice reacting to the rushed sensation of an accidental flip by purposefully flipping at high speed or with only one hand on the shaft. Don't use your roll to get in over your head skill wise. Being in control is much more fun than counting fish!