This thechnique involves getting a pair of sneakers, prefably ones with soft synthetic liners and a pair of thick tube socks.
To make a really stimlating sneaker masterbation toy simply put a pair of tube socks into the sneaker and pour in heaps of lube in between the socks and the toungue of the sneaker. Then put your penis in between the sock and the toungue.
I find shampoo or hair conditioner is a excellent lube.
You can even try lubing the top of the sneaker between the toungue and the laces. The mesh material on most nikes is very very stimulating and will gaurantee an explosive orgasm. Insert your penis from the front so the toe cap can rub your balls while you masterbate it with your shoes.
I showed this to my mate, and he loves it!!