Err I suggest you have a good read of the "info post" sticky at the top of this forum.
Then read a good book about puberty from the school library, then think again about having sex or showering with someone.
Also see your doctor about birth control. Just in case you are fooling around one day and "get carried away".
To get pregnant sperm
has to enter the vagina. No sperm in vagina - no pregnancy.
So the only real safety tip (as regards avoiding pregnancy) is do not get any sperm inside your vagina.
***ladies she asked before not after the fact so lets not be too hasty***