Get yourself hard the way you're used. If you haven't already, use some lube. Get both your hand and your cock silky soft (I love the silky lubes). When you're a good strenght, make sure your index and middle finger are nice and greasy. Pull down your foreskin (if you have any ;-) ), make a 'peace sign' with your two fingers and rub them underneath the edge of your cock's head.
Might take a while before the sensation starts. Make sure to apply some pressure and don't stop it feels like tickeling. The reward will be great!
Let me know if you liked it.