4. Decide now when it's OK for you to have sex.
This may sound weird because you probably don’t want to think about your teen having sex, but thinking about it now can make a difference, experts say.
"Teens aren't great at thinking on their feet," Holmes says. When they work out ahead of time how they will turn down drugs, drinking, sex, or other challenges, they are much better at matching their actions with their values.
"Making a plan ahead of time can delay intercourse up to 18 months," Holmes says.
But talking about it happening doesn’t mean you’re being totally lax or giving your teen a free pass. Be clear about what you expect. For example, you might say, "I want you to delay having sex until it can become part of a meaningful relationship."
Also make sure your teen knows about STDs and how to prevent them, where to get condoms and birth control (including emergency contraception), how to use protection, and how to see a doctor even if he or she doesn't want you to know that they are going, Holmes says.
If that feels as if you're giving a mixed message, she suggests saying, "I want you to have this information because you will most likely need it yourself one day, but you also might use it to help a friend now."
5. Practice how you will say "no."
Even adults have trouble saying "no" sometimes. Rehearsing ahead of time cuts down on the stress of having to say no and thinking of how to do it. Point out that having a plan will give your teen more resolve and power in sticky situations, says Carl Pickhardt, PhD, a psychologist in Austin, Texas, and the author of Surviving Your Child's Adolescence.
Most likely, your teen can come up with their own ways to say "no." But when caught by surprise, Pickhardt says, a good standby is to say, "'Not right now.' In other words, 'I'll do what I like when I want to do it, not when somebody else wants me to.'" This response can also cut down on people asking "Why?"