You may want to briefly HOLD or interrupt the advance of the shot list, by pressing the HOLD button (or pressing the Command key on the keyboard) momentarily. 

You may also use the OFF BOOK button to lock the system in a hold state which will be cleared when you take the next shot via the keyboard, or when you switch the OFF BOOK button off. So the OFF BOOK button and the HOLD functions are identical, but where HOLD is momentary, OFF BOOK stays latched until you toggle it off or manually advance the shot list.

And finally, you may program an OFF BOOK state into your shot list by entering [HOLD] in the shot description. This is useful at the end of scripted segments and the end of your show file.