1. This may be a stereotypical tool for female masturbation, but it can work pretty well for men, too. If the shower head is detachable, you can pull it down and use it in any number of ways. You might try direct, steady pressure against either the front or back of the penis. In a lot of cases direct pressure can be a little strong, in which case you might soften it by placing a washcloth over your penis to soften the sensation. A shower curtain can also work here. But that's just the beginning.

2. You can also move the head up and down so that the water provides the sensation of stroking the shaft of your penis.

3. Or you can roll the nozzle from side to side, so that the spray of water washes back and forth across your penis. Personally, I find this motion more enjoyable than either of the first two options.

How about this for the ultimate technique. You don't need to do anything, and you don't need any tools at all, not even your hands! Just a little imagination and focus is all it takes. Not that it's particularly easy to do. There are a few tricks that seem to help, including: keeping a strong mental image of something arousing, focusing intently on feelings of arousal, breathing control, and already being fairly horny to begin with. Everyone works differently, though, so something that helps one person may distract someone else. Even under the best of conditions it's not easy, but it is definitely doable.