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Sometimes when your boyfriend kisses you, you may not be expecting it, like if he comes up behind you. If you blush easily and can feel the heat rising to your cheeks, there may be nothing you can do to stop it. Trust that the moment will pass quickly. You could even call attention to your reddening cheeks by saying something like, "I can feel my face getting hot!" Chances are, your friends will laugh a little and you can move on from the moment. You'll have explained the blush and can redirect the attention elsewhere in the group, which should help your skin calm down quickly. If you want to, it's okay to return the kiss, but try to keep it short so your friends won't feel uncomfortable. This should just be a peck and shouldn't involve french kissing or heavy petting. Remember, you're in front of other people so it's not the right time to move into a really intense, passionate kiss. If your relationship is new, this can be a great way to get other people used to seeing you together, too. It may be really exciting to see and kiss your boyfriend, but if you're with other people, you should try and be in the moment with everyone. It's okay to hold hands or sit next to each other, but avoid keeping your lips locked for more than a few seconds. Be sensitive to the others in your group. Maybe you have a friend who just went through a breakup or who is crushing hard on someone who doesn't feel the same way. No one wants to watch you and your boyfriend slip from a quick kiss to a full-on make-out session. That can make people feel alienated and uncomfortable, which definitely isn't how you want people to feel when your boyfriend is around. If your boyfriend seems like he is moving toward a more passionate moment, gently end the kiss and pull back from him to signal that you're done for the time being. In general, hand holding is a really acceptable form of public affection, and holding your boyfriend's hand after a kiss will show him that you feel fondly toward him. Especially if you are new to kissing in public, this can affirm that what he did was okay with you. If your boyfriend just joined your group and someone was already sitting beside you, ask if it's okay to change seats, or just have your boyfriend sit somewhere else. There will be plenty of time for handholding later on! If you do decide you'd like to spend some alone time with your boyfriend, go for a short walk together. This could give you some extra time to connect or kiss more without making anyone in your group feel uncomfortable. If you do go off alone, make sure you rejoin the group before too long so nobody starts to worry about you. Try saying something like, "John and I are going to go for a walk to catch up, but we'll be back in a little while."
Let yourself blush or be surprised if you weren't expecting it. Kiss your boyfriend back for a few seconds. Return to the conversation or activity you were doing before the kiss. Avoid making out in front of your friends or ignoring them. Smile at your boyfriend and hold his hand after the kiss. Leave the group if you want some one-on-one time with your boyfriend.