Are you a girl wanting to know? Just explore you'll find what you like. If you're a guy... sometimes its a turn on to the girl if you ask how she does it so you can know what she likes.

Quietly so you dont wake him up, lol

By rubbing their clitoris, fingering themselves, etc. If you are interested in female ejaculation, here's an interesting article on how to learn how to do it: http://abbys-sexual-health.com/articles/female_ejaculation.php

Depends on the woman, dear. Some use the shower head- they may put it on the pulse setting and move it around to get themselves off. But some will just lay under the faucet and let the water run over their area and think about something/someone who arouses them in that way. There are vibrators that people can use (including The Rabbit). These move faster than a guy will inside the vagina (or one may use it for anal), so they'll like that feature sometimes. There are rubber penis toys one could buy as well- they come in all shapes and sizes, and this way, she can get just what she wants; depth, width, angle, speed, pressure. Beads have been used as well- quite like the toys listed aove this sentence, but these are beads instead. The old fasioned way would be to finger themselves of course. Some people like it done dry, but a lot of ladies like it when their wet and opened up (due to stimulation) because you can fit more in. She may just massage her area with her palm, too. To get an orgasm, she'll need to stimulate her clit, as this is very helpful. However, oral is great with that as well, and she can't do that herself. So I've heard of people using rose petals, silky wash cloths, tissues, or a gelled up finger. I could say more, but I think that covers enough of the basics. You can ask more of course :)

anything can even for guy