• Automate good decisions. Whenever possible, design an environment that makes good decisions for you. For example, buying smaller plates can help you lose weight by deciding portion size for you. 
• Subtract the negative influences. You can make it easier to avoid unhealthy foods by storing them in less visible places. (Foods that are placed at eye level tend to be purchased and eaten more frequently.)

We tend to believe our habits are a product of our motivation, talent, and effort. Certainly, these qualities matter. But the surprising thing is, especially over a long time period, your personal characteristics tend to get overpowered by your environment.