chastity cages do help and can be a lot of fun. I am wearing one right now! They are definitely much much better when you have a keyholder though. Did you meet to suck your friend's cock yet?
Good! Don't touch your cock! Let the anticipation build up and swell inside of you. You will feel SOO good and get SOO HARD once you feel him in your mouth. Make sure you cum with his cock in your mouth so that you always associate sucking cock with pleasure.