Using the mouse, a cue can be triggered by double-clicking it, or clicking on the Go Next
button.
Using the keyboard, the following commands can be assigned keyboard shortcuts by going to Options > Keyboard Shortcuts
Fire Next Cue
Fire Previous Cue
Step Up (default option + cursor up)
Step Down (default option + cursor down)
Go to top
Stop All Cues (default cmd + escape)
Only the list with the Armed button enabled will receive the commands.