It is important to write down both the pros and the cons of the behavior that you want to change. If you only write down the negatives then the positives will stay in your subconscious and work against you. This is why it is important to be conscious of both the positives and the negatives of the problem behavior.
The way to do a formal CBA is to get out four sheets of paper and write out both the pros and the cons of keeping or changing the behavior on them as you can see in our samples. People also do informal CBAs any time that they discuss the pros or cons of a behavior.