1. Open iMovie located in /Applications/iMovie
  2. In the Projects browser, click Create New. If you're currently editing a movie, click the Projects button in the toolbar, then click Projects again to open the Projects browser.
  3. Click Movie (see below). Your new project opens, showing the browser, the viewer, and the timeline. You can also click Trailer to use built-in templates to create a trailer with your own videos and photos.

    iMovie: Create new movie project

  4. After creating your project, add clips from events in the Libraries list, or add video clips and photos from the My Media tab:

    iMovie: Drag and drop clips

    You can also import video clips, photos, and other media located on your Mac's hard drive or cloud storage:

    iMovie: Import media

  5. To start creating your movie, drag clips from the iMovie browser to the timeline of your project. You can also drag clips into the timeline from the Finder and from the Desktop of your Mac:

    iMovie: drag and drop clips to project timeline

  6. After you add video clips and photos to the timeline of your project, you can make a clip longer or shorter, change the sequence of clips, or split a clip into two separate clips.
    • To zoom in on the clip, choose View > Zoom In, or press Command–Plus sign (+) or pinch the trackpad. When you zoom in, you can see more detail in the clip, which can make it easier to edit.
    • In the timeline, hover your pointer over the beginning or end of the clip that you want to trim until your pointer becomes the clip trim tool: iMovie: Clip trim tool . The arrows indicate which directions you can trim the clip:
    • To make the clip longer, drag the edge of the clip away from the center of the clip.
    • To make the clip shorter, drag the edge of the clip toward the center of the clip.
  7. You can change the sequence of clips in the timeline to change when a particular clip appears in your movie. With your project open, click the video clip or photo in the timeline, then drag the clip left or right depending on where you want the clip to appear in your movie:
    • If you want the clip to appear earlier, drag the video clip to the left, then release.
    • If you want the clip to appear later, drag the video clip to the right, then release.
  8. You can also move multiple clips at once:
    • Hold the Command key as you click each clip you want to select, drag a selection rectangle around the clips, or hold the Shift key as you click each clip.
    • Drag the clips to a new location in the timeline.
  9. Split a clip into two separate clips:

    When you split a clip, you can adjust the duration of each section, remove unwanted sections, or add different titles to each section.
    • Scroll in the timeline to position the playhead (the white line) where you want to split the clip.
    • If necessary, choose View > Zoom In or press Command–Plus sign (+) to zoom in on the clip.
    • To split the clip, choose Modify > Split Clip or press Command–B .
  10. After you split a clip you can add transition effects such as cross fades and dissolves:

    iMovie: Transitions