It makes things bigger, they're great on shaved bollocks. Pull the foreskin right back, put as many as you can get on the head of your cock, then pull the skin over and leave them, you'll love it.
It's a lovely feeling. Try and get one or two down inside the piss hole. But whatever, cover the head of the cock with them and pull the foreskin over and let them do their work and give you pleasure. They're also great on a shaved scrotum. Stinging nettles are also fantastic, as is toothpaste. Enjoy!