If your Mac has a built-in camera, you can record your movie directly into iMovie.
Click “Create a new project" and give it a name
Make sure the Video format is set to ‘iSight’
You should see a window that looks like the screenshot shown here (iMovie01). Note the viewer and its controls on the left, the clip library on the right, and the timeline at the bottom. We will refer to these throughout the tutorial.
Click on the Camera icon (labeled as ‘Switch to camera mode’) and choose ‘Built-in iSight’
You will see what the camera sees in the Viewer along with a button labeled ‘Record With iSight’
When you are ready to start your video, click this button to begin recording
When you are done, click the button again to stop recording
You will see the video you just made appear as a clip in the Clip Library