I usually don't stutter when I first meet people, so I guess I hide it unintentionally, but I always tell them just so they know that I sometimes stutter when I speak to avoid any kind of "jokes" or anything they may say or do in response to my stuttering if they don't know about it. When people aren't aware of mu stuttering they might see it as something cute or funny and make a joke about it or feel uncomfortable so they'll try to complete my words or interrupt me, so I always give them like a heads up that I may stutter when I speak and that I can't really control it sometimes.