Help with my best guy friend?

So me and my my best friend have been friends sense 6th grade. We did not want to be friends then my and his friend pushed us together she was awesome. We joke. Play around. And always hang. He asked me out and I said yes. I am 15 and he is 16. We hang out and tex and do everything together, while we still have are time apart with are other friends. The only thing is is that when we just chill. I' sit in his lap or w will try and snuggle. We just don't quiet get it. Like we know how, and are body's fit perfect together. Its Just we aren't sure how to. If tat makes sense. When we hang out my parents or his are at home sometimes. We both think its not right for me to be sitting on his lap while his younger siblings and my younger siblings and are parents are watching us. We are both waiting till after marriage to have . We want something that is a better way to sit with each other, then me on his lap. Any ideas on how we can?