For this to work it's important that you want to change the habit, and that the rules work for you. They shouldn't be too complicated or too restrictive. You shouldn't cheat. If you must cheat, add a rule that allows exceptions, such as allowing yourself to go out for coffee once a month for no particular reason.
It does take some self control to get started, but for me rule based decision making is a way to put self control on autopilot.
Edit: I wanted to add an example of an unsuccessful rule. At one point I tried a bedtime alarm in an attempt to get more/better sleep. I set my alarm clock for the time that I should stop doing whatever I'm doing and start getting ready for bed (10pm). It didn't work for me because it was inflexible. Sometimes I wanted to finish whatever I was doing, or sometimes I wasn't tired. I have yet to find a good way to consistently get to bed on time.
One more thing: Rules don't seem to work to prompt me to do something. They are only good when you face a decision and need to choose what to do. For example, it won't work to make a rule to vacuum once a week. I'll forget. A calendar or reminder system is better for that. So rule-based decision making is good for breaking habits but may not work as well for making new habits. With some creativity you might still be able to make it work. For example, if you want to exercise more, get a pull-up bar and every time you walk through the doorway with the pull-up bar, do some pull ups.