You don’t have to make a big deal about it! A simple sentence at the start „Before I start, I want to mention that I have a stutter so please be patient.“ goes a long way. First, it reduces the pressure you put on yourself, because now you know in your head that you are allowed to stutter. Second, the audience does not misinterpret your blocks with something else. In my experience, most people have no idea what stuttering is, and they think that you are just nervous or in the worst-case, stupid. Don’t make a big deal out of it, but don’t hide it.