First time

My bf & I are 25yrs old and have been dating for a year. We're both virgins. Sex is just something we take very seriously. We're thinking we may finally do it in the next few months. I'm not keen on putting meds in my body. I can't discuss this with my mom. She's very old fashioned and the first time is a surprise lol. Anyway, what precautions do you recommend? We've thought about nfp.