I feel for you. It's not easy for me either. Your best bet is to be upfront about your stutter and tell them about it at the beginning of the interview. This takes away a surprising amount of the fear and anxiety on your end (at least for me it does). After that, it's up to you--use whatever techniques work, or just let yourself stutter through it. What do you want from this interview? Keep that in mind and try your best to go for it. I'm hoping for the best for you!