A key benefit to recording in GarageBand is the tempo function. The tempo, or speed, of the song is measured in beats per minute, and can be created before you even begin laying down tracks. GarageBand tempos range from 40 beats per minute (extremely slow) to 240 beats per minute (extremely fast). Once you have selected your desired tempo, you can turn on a metronome that plays beats to the tempo you have chosen.
Create a new music project in GarageBand.
Name your song in the New Project pop-up box. Select where you want to save the project.
Move the tempo slider in the New Project pop-up box to set the desired tempo. Select the appropriate time signature for the song, and designate the key if desired. Then click "Create."
Select "Control" in the GarageBand menu once you have created the new project. To change the tempo, go to "Control" and select "Show Tempo in LCD." Click on the tempo on the LCD display to change.
Turn on the metronome by selecting "Control" from the GarageBand menu and then clicking on "Metronome," or press "CTRL-U" on the keyboard to turn on the metronome.