I was nervous presenting the first time I presented too. Make sure you talk about any challenges you had during the rehearsal process and performance run. Did you have any really crazy scene changes or costume changes during the show? Was there a large cast? Did any understudies need to fill in? Did any emergencies occur? If so, how did you handle the situation? Did the script have any unique challenges like script rewrites? For example, I watched a stage manager's presentation for The Drowsy Chaperone, and he highlighted how an actor had to roller skate while blindfolded during the show.
Also, the two professional stage manager respondents might ask you questions about your prompt book or the challenges you describe during your presentation.
Break a leg!