Editing is essentiell. Nobody asks for 30min-single-shot-talking-heads. 

You wrote a script and edited it.

The structure of your script defines the edit.

Edit cleans, tightens, makes things simple.

Learn all features of iMovie BEFORE you launch your first episode.

Watch the tutorials, visit an Apple-Store (as a start.. ) for a training-session.

iM09 allows ultra-fast editing - and ultra-fast making errors.
don't do trial-and-error-editing. think first.