The next much-needed exercise is called riding the edge! It will greatly improve your self-control.
Get yourself to the edge again but this time, slow your strokes down and keep yourself right at the edge of cumming without going over!
Keep going like this, making your strokes lighter and lighter until you can keep yourself on the edge with 1 finger.
Once you can do this, keep yourself at the edge and count to 10
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Now stop touching your cock, count to 30 and if you havent squirted...