I'm not sure of the 'rules' of writing an interview but it can be really fun and a little freeing in a way cause in an essay you need to reach conclusion, keep it cohesive, build your argument solidly etc whereas in an interview you have two points of view. I'd say:
-If it's for radio, back announce a track with a title that's pertinent, can add some humour too, allows your announcer to say something like "and speaking of holidays, we have with us today blah blah"
-give your announcer some sound knowledge or at least enough intelligence to have insight and challenge. I think it's totally wasted words and effort to have them asking "So Miff, what is this novel all about?" or something to that effect. Have your announcer pose challenging and interesting points that the guest speaker can respond to. Have them studied the unit in hsc/seen the play/had a phone in last week where students asked certain things so they can say: I understand that commonly, students think that Gow's trying to ...", anything that will give them intelligent stuff to add. So I don't know the play well or the thesis, so this'll sound like crap, but something like:
"Interviewer: In the version of 'Away' that I attended, the final words about dark purpose and death were delivered by Tom, an ending Wherrett preferred for its dramatic irony. Gow's own interpretation is powerful and spare but it's far less sentimental. Do you think the text is consciously trying to keep this sort of sentimentality under control. I mean, are the elements of comedy and tragedy held sufficiently in check?
Guest speaker: Oh definately Miff, I mean I like a good weep as much as the next person but I can't abide 'sap'. No Gow had tred that very fine line well. Take the scene on the beach where ....."
-Have them argue points. You can have fun here presenting different views cause in the end they can say: "Well, we'll have to agree to disagree on that one Tom, because to me the storm was not just a bit of bad weather, it was of cosmic significance. But if we can go on to another point ....
-If it's radio and it's JJJ or something you have to make it sound like that so you can have humour but again I think it's a waste of time to attempt any humour that's not related to the body of the work, just have them exaggerate a point or frame something a little flippantly occassionally to keep it light.
that's all I can think of right now