Bored in my relationship

I’ve been with my boyfriend 3 years and everything’s getting a bit samey, the sex, the things we do and it’s not as exciting as it used to be. I know this is bound to happen but has anyone got any ideas of how to add some excitement to our relationship again? Any nice ideas of things I could do for him? Anything I could do during sex to spice it up? Any ideas really, thanks girls :)