Previewing the effects
It’s time to preview all of the effects together.
Click the Explore Hawaii tab in the Timeline panel to switch to the main composition. Press the Home key or drag the current-time indicator to make sure you’re at the beginning of the time ruler.
Make sure the Video switch () is selected for both layers in the Explore Hawaii Timeline panel.
Click the Play button () in the Preview panel, or press the spacebar, to watch the preview. Press the spacebar to stop playback at any time.