Hang on to a sturdy object for balance and stand on a dumbbell handle, preferably one with round plates so that it rolls as in this manner you have to work harder to stabilize yourself; thus increasing the effectiveness of the exercise.
Now roll your foot slightly forward so that you can get a nice stretch of the calf. This will be your starting position.
Lift the calf as you roll your foot over the top of the handle so that you get a full extension. Exhale during the execution of this movement. Contract the calf hard at the top and hold for a second. Tip: As you come up, roll the dumbbell slightly backward.
Now inhale as you roll the dumbbell slightly forward as you come down to get a better stretch.