Step 1: (Return to) Zero
Pressing the Z key on its own returns the playhead to the top of the song (the Return key does the same thing). Alt+Z takes you to the end.
Step 2: Zoom
GarageBand’s arrange window zooms horizontally, and this is achieved by dragging the slider beneath the track list. The shortcut is Alt+Cmd+Left/Right arrow.
Step 3: Go to region start
Hitting the Function key + Ctrl + Left arrow will whizz the playhead to the start of the selected region. Tap the Right arrow to take you to the end of the region.
Step 4: Shift window
Another display trick is flicking the arrange window along by the visible width of the timeline. Hold down the Function key and flick the Up/Down arrows.
Step 5: A for Automation
Hitting the ‘A’ key at any point reveals the automation curve for the selected track, equivalent to clicking the small triangle button in the track header.
Step 6: O for over and over again
Select a region and hit the ‘O’ key and GarageBand will loop the region to fill the space up until the next region or the song’s end, whichever comes first.
Step 7: Split & Join
Regions can be cut at the playhead position using the ‘Split’ command – the shortcut is Cmd+T. To repair a split, use the ‘Join’ command – the shortcut is Cmd+J.
Step 8: Record and cycle
Hit the ‘R’ key while the song is playing to drop into and out of recording on the currently selected track. The ‘C’ key toggles the cycle mode on or off.