If you’ve ever regretted the extra cookie, skipped the workout, or said something in the heat of the moment, you’re not alone. Here’s how to build real self-control.

Monitoring is the easiest and fastest way to improve self-control, said Roy F. Baumeister, a professor emeritus at Florida State University who has studied the topic for three decades.

However, when we or others fall short of these ideals, it is easy to fall into the trap of "willpower- shaming "—judging ourselves or others harshly for an imagined lack of self-control. This ...