Don't be terrified, sleep properly. I did this for my first job. Print out copies of your resume,, pick out your outfit and appear there looking very dapper. Be early so you aren't competing with others especially in the beginning when they are looking to fill slots. Go to the bottom 3-5 booths that you know you will never work at and stutter voluntarily, advertise, disclose, all that jazz. Just make it real and be free. Get it out of your system. Practice on them. If they react its on them and you don't care that much anyway. Then go to your top 5 booths where you would absolutely love to work and by that time the anxiety will be over and you will be in a much better place mentally. Probably you won't even stutter at all, and we are praying for you that you get hired on the spot.