pretty much the same way you would in a bed...exept dont fill the water too high and it might be a good idea to put a pillow on the edge so your head isnt resting on a hard surface. also remember you can still get pregnant and/or a std/sti in the water, so make sure he uses a condom
well, i've heard it's difficult to use a condom in a shower because it slips off.. which i don't kniow if it is true or not.. and i have had sex in a bath but apparently it's not good for the woman..
If you are talking about w/ someone then just do it, if you are talking about "relieving yourself" then do that in the shower or something.
