Position yourself between his legs and wrap your hand around his penis, with your fingers at the site of his belly and your thumb at the site of his scrotum
Move your hand away from his body. When you arrive at the tip, don’t go back the same way. Remove your thumb and turn the palm of your hand around his glans, moving your fingers to the front. So your fingers are now at the site of his scrotum and your thumb is at the side of his belly. To go from the tip to the base of the penis and up again. Then you turn the palm of your hand around his glans again and move your fingers to the back. So you change the position of your hand but keep in touch with the penis all the time. Use a lubricant.
It must be a smooth movement from the tip to the base and back, before nuzzling up with the glans. The most important part of this technique is the contact between the palm of your hand and the glans of his penis.