I sell tree work and I know I can't get hung up on it because it doesn't help so I ignore it.  It was very hard at first but now I can even say my name with ease again.  That surprised me all over again.  I just don't think about it.  I wanna get the right number, let them know we are trustworthy by explaining our policy of not asking for a deposit or anything and not getting paid until we are done and they are happy.  It took a while but it becomes second nature after getting through the fear and just persevering, just keep going.   Stuttering wise I try not to stop and block but try again, breath into it kinda to keep it from being entirely locked up if I have to, but what ever the case, try not to give it a second thought.  They'll get it and I think they tend to be surprised and impressed that I keep going with a kind smile and as though nothing happened.  Lately my stutter is very minimal if non-existent to them during sales..though I feel it, because I pull back a few times and try again I don't think they notice sometimes.  Other times it's very obvious.  Either way, don't care.  We keep on living and have to have some control over our own heads.  We won't always be happy but that's what makes happiness as great as it is because we know the other end of it that comes and goes all the same.