Here are the steps to cut a clip in iMovie:
1. Open iMovie and select the project you want to work on.
2. Select the clip you want to cut and drag it into the clip viewer.
3. Hover your mouse over the video in the timeline to the place you want to cut the video.
4. Right-click on it and then use the Split Clip option to trim video in iMovie. You can also use the Command + B to quickly make a cut in iMovie based on your need.
5. After the video cutting, you can select and remove the unwanted video clip(s).