The action is the habit you want to create; the cue is your trigger, your reminder. We need a reminder because one of the main obstacles of self-discipline is forgetfulness. Until your chosen activity becomes an automatic habit, you will need reminders to do it. You cannot depend on your memory for this. You need an effective cue to remind you. If you have followed the previous steps, by now you have an effective cue and know exactly what to do when you see it or hear it.

Whatever reminder works for you is okay. You can get creative with it, and also change the reminder over time if it ceases to be effective. There is only one rule you need to observe for reminders to work. It is so simple and commonsensical that it’s even embarrassing to write. But common sense is not always common practice, so here we go:

Once you get the reminder, do the action.

The most amazing cue and the best reminder system in the world are useless if the moment the cue happens you ignore it and instead say to yourself, “Great, I’ll do this later” or “I’ll get to it soon”. 

Know that once you get the reminder, you have just two options: do it and get a +1, or ignore it and get a -1. So remember the golden rule: once you get the reminder, do the action.