Consider putting yourself back on cash. If you think you shop impulsively because it is so easy to use plastic, try to give yourself a cash allowance every week. You may go over the allowance, but you will have to go to some effort to replenish it. This can be a great way to get a handle on spending.
When most people hear about creating a monthly budget they run the other way in fear. They just don't know where to start. It certainly wasn't something that most of us where taught in school. However, it would have been more useful than some history lessons.