Variety and pacing play a role in every decision the video editor makes. Here are some common tricks professional editors use, which you can also use in iMovie editing.
One of the first tasks you’ll encounter when editing your footage is choosing how to trim and chop up your clips, as described in Chapter 5. Even when editing home movies, consider the Hollywood guideline for tight editing: Begin every scene as late as possible, and end it as soon as possible.
In other words, suppose the audience sees the heroine receiving the call that her husband has been in an accident, and then hanging up the phone in shock. We don’t really need to see her putting on her coat, opening the apartment door, locking it behind her, taking the elevator to the ground floor, hailing a cab, driving frantically through the city, screeching to a stop in front of the hospital, and finally leaping out of the cab. In a tightly edited movie, she would hang up the phone—and then we’d see her leaping out of the cab (or even walking into her husband’s hospital room).
You might keep this principle in mind even when editing your own, slice-of-life videos. For example, a very engaging account of your ski trip might begin with only three shots: an establishing shot of the airport; a shot of the kids piling on to the plane; and then the tumultuous, noisy trying-on-ski-boots shot the next morning. You get less reality with this kind of tight editing, but much more watchability. ...