For most people, deciding when to have sex—the first time with a new partner, or especially the first time ever—is a significant decision. Becoming sexually intimate with someone can change your relationship. Sometimes, it’ll even change you.

Plus, it’s hard to tell what the effects will be. For some people, sex, even the first time, isn’t that big a deal. For others, it has much more impact than they anticipate. You might feel a profound connection with your partner (even if you don’t want to). Or you might feel empty, or disappointed, or used. Having sex might or might not change your relationship status—you might become a couple, or you might break up. When you open yourself up to someone, you open yourself to so many possible outcomes.

None of which is to say that sex is bad. In fact, it’s often wonderful. But it’s much more likely to be wonderful if the person, the timing, and the situation are truly right for you.

If you think you might be ready but you aren’t quite sure, here are some factors to consider. Ideally, all of these will be true for you before you sleep with someone new:

You’re excited about the idea. It’s common to be anxious before having sex with someone the first time. But if you’re scared or dreading it, that’s a strong signal that this isn’t the right time or person for you. You should actively want to connect physically with the person. Is your gut on board with the idea of having sex?

The two of you have arranged birth control and STI protection. It’s awkward to talk about BC and preventing STIs, but that’s nothing compared to how awkward and awful it’d be if someone got pregnant or got an infection. The most effective forms of birth control take some planning, so give yourself time to get them before you have sex. Condoms are easy to get but can be inconvenient in the moment. Use them anyway. If you’re not comfortable enough with the person to talk about these important things, are you sure you’re comfortable enough to have sex with him/her?

You can trust to person to be discreet. If you do the deed tonight, would you want everyone to know tomorrow? Can you be sure your partner won’t brag to the whole world? It’s hard to tell for sure. If the person has told private information about friends or past partners, that’s a red flag. But if you’ve told personal or embarrassing things before and s/he’s kept your secrets, that’s a good sign.

You’re ready to be seen naked. It’s really vulnerable to be completely naked in front of someone. Are you ready to feel that exposed? Can you trust this person to delight in your body and not say anything critical? (Because every body is imperfect, and there’s no place for body-shaming in an intimate relationship.)

Your partner has shown interest in your pleasure, not just his/her own. For some people, especially some young men, sex is all about them. They may care about getting themselves off and not give much thought to what’s going on for the other person. This usually results in a disappointing or even painful experience for the partner. Most women enjoy sex a lot more with a partner who knows they need a lot longer to warm up and is willing to take the time. Is your partner curious about what gets you excited? The more he or she has demonstrated interest in what feels right and exciting to you, the better your intimacy is likely to be (both physically and emotionally).

You’re pretty sure the person will still be around tomorrow. I’ve talked with several young women who finally decided to have sex with someone they’d been seeing for a while and trusted, and then were devastated to be dumped right after. Maybe the guy freaked out because he was afraid of commitment (even if she didn’t ask for one) or maybe something else was going on with him. Whatever the reason, that hurts. There are no guarantees, but it helps to talk through your relationship status before you sleep together. Are you “a couple”? What expectations will each of you have after you have sex? How will sleeping together change things?

You’re ready to risk developing feelings (or deepening them). Sometimes people think they can “just have sex” and leave the feelings out of it. Sometimes it works that way, but often it doesn’t. Sex is so vulnerable and powerful that it’s easy to get emotionally attached to your partner. If you did “catch feelings,” is this someone you’d want to fall in love with?

You’re positive you’re doing it because you want to. Sometimes people agree to have sex because the other person wants it, or friends are saying they should, or it’s been x amount of time and that means you’re “supposed to.” None of those mean it’s right for you; the right time has to come from inside yourself.

External pressures can be strongest for young people. But “everybody’s doing it” is not only irrelevant, it’s wrong. Despite what you hear, a lot of people aren’t having sex. There’s a lot of talk, but not as much action as you’d think. I surveyed 900 young adults aged 18 to 25 about how many partners they’d had in their lives—and the answer may surprise you. The median number was three; the most common number was one. So if you decide to wait until your time, you’ll be in good company.

You think it’ll be a memory you’ll be happy about. Especially if you’re considering sex for the first time, know that you’ll probably remember it for your whole life. Is this the person and the situation you want to remember? Whether you’re new to sex or not, will going to bed with this person tonight leave you feeling good about yourself tomorrow?