How do I tell my boyfriend about my kinks?

We’ve been together for quite a while and I don’t know how to tell my boyfriend that I’m into more things and have more kinks than just being tied up during sex. I don’t know how to bring it up while we’re talking about sex because he’s not into trying a lot of different and new things in bed. I don’t want to overwhelm him by bringing this up a year into us having sex.