Being more open helps a lot! While being anxious (used here in the general, non-medical sense though I do also have GAD) doesn't cause stuttering it can exacerbate it for lots of people. Ironically one of the biggest sources of anxiety for many stutterers is attempting to conceal their stutter or at least minimize it because they don't want people to judge them. Just telling someone takes some of the pressure off because now it doesn't matter if you stutter. It also moves things from "I better not stutter" to "you shouldn't find anything shameful about this".