If your the same as you were before you had sex, and you don't act any different, they'll never know, unless they see evidence, or catch you, or hear you.. Make sureyou dispose of the condom if thats the birth control your using, or make sure they're not home, and if you take a guy into your room, make sure if your mom comes to check on you guys, your not doing anything, or she migth ask later, and be saspicous. Or, even better, don't do it at your house.
Be honest with them trust me we like that better, I didnt like the idea of my daughter having sex but when she came to me we went to the gyn doctor and she is now on the depo shot, you have to remeber it will be your parents that will stand by you and help you through what ever can come of you having sex, preg. and disease so let them help you figure the best way to prevent them.
1. tell them.
2. hide every bit of evidence possible. (messy hair, hickeys, etc.)
3.Dont do it everyday, or they'll get suspicious.
4.Dont get pregnant.
N there ya go, just dont go with a buncha different guys! i know you wont :D
Don't bring boys round, don't stay out for too long, don't do anything that might make them question where you are going because then you will have to lie which is worse than just not telling
Just don't do it in the first place, then it'll be easy to hide.
Make sure you don't have the distinct smell of ba'dussy on you.
Don't tell them. Hide the evidence. Eg. Contraception.
Just don't tell them.