There are a number of things in iMovie that are less than obvious and benefit from further explanation. To change the name of a project from the default ‘My Movie’, either click Projects above the libraries list and then click the project’s name, or click All Events and then click the project’s name. To assemble clips in a project without adding them to the timeline, drag them from the library on to the project’s name under Project Media. If you find that your built-in microphone doesn’t record any audio or register on the meter, go to System Preferences > Security & Privacy > Microphone and make sure the iMovie checkbox is ticked.