For a dildo :
I use a bit of blutack moulded in to the shape of a cock.
Then i wrap it in a condom. However, If you dont have a condom, use clear plastic food wrap and an elastic band. The good thing is, you can mould the blutack to whatever shape cock you want. Believe me. It feels SOOOOOOOO good.
For another masturbation method (for girls):
I sit in the bath and i run some water. Then i put my pussy up against the water and i let it trickle down slowly... Orgasm in seconds...