Hold Alt/Option (⌥) while dragging to snap the clock time to 5-minute intervals.
Hold Shift (⇧) while dragging to snap the countdown time to 5-minute intervals.
Undo & Redo
You can undo changes by using the default OS X shortcuts ⌘ + Z, and redo with ⌘ + ⇧ + Z.
While you are still dragging you can drag back upwards to cancel your reminder. If you have the little description window open already then you can press ESC to cancel it.← Tips & Tricks