When I was younger, about 15 or 16 I discovered masturbation from a comic book that I read called Dirty Plotte. I later met the artist Julie Doucet who spoke only French (Canadian) and I wish I could have relayed to her exactly why her comic changed my life.
The book wasn't particularly pornographic but it dealt with adult themes and the main character felt the need to masturbate in the sink with the water running on her clit. I thought this was funny, but it made sense considering I had been having feelings of wanting to touch my clit but thinking that I'd get caught and I'd be considered bad for doing it. The bathroom would be the place for ultimate privacy.
So one day in the shower, I did just that...I lay there and let the shower run over my clit. Having one strong stream of water on my clit made me cum so that my legs were shaking and I was convulsing into an amazing orgasm.
It came to a point when that just wasn't enough stimulation for my clit so I decided to experiment with the faucet. I would lay with my buttocks to the wall with my legs straight in the air and let the warm water run over my clit. I was able to cum really quickly and my legs stretched straight up and I'd have a pulsing orgasm over and over and my pussy would pulse over and over for several minutes.
I kept experimenting with ways of increasing the sensation since it became an addicting habit every time I showered. I'd take little travel shampoo bottles and put those in my pussy while I ran the water over my clit. It would hit my g-spot and I'd actually have to hold in my moans if someone else were in the house. If I were alone, I'd moan loudly and the orgasm felt more intense.
After I had my kids, my nipples became a part of my arousal. I'd rub lubricant on my fingers and play with my nipples (propped up on my elbows helped keep the clit and my g-spot centred) When I didn't have any lubricant available I'd just try and lick my nipples or use my spit to make sure the slippery feeling of the stimulation was there.
I continue to use this technique to masturbate because I can usually achieve orgasm in just a couple of minutes, it's quick and clean, and no one has to know....unless they suspect why you are running the faucet rather than just turning on the shower.