Atomic Habits
by James ClearA must read if you haven't already but also a good book to refresh your mindset going into another year.
Callouts: Habits are the compound interest of self-improvement. Small, incremental changes can lead to big results over time.
It's easier to change your environment than to change your mind. By altering the cues and rewards that drive your habits, you can make it easier to form good habits and break bad ones.
To build a good habit, make it obvious, attractive, easy, and rewarding. To break a bad habit, make it invisible, unattractive, difficult, and unrewarding.
To achieve your goals, focus on the process rather than the outcome.
To overcome setbacks and stay motivated, use the "2-Minute Rule" to start small and build momentum, and embrace the idea of "small wins" to celebrate your progress.
To develop a growth mindset and cultivate a culture of continuous learning, embrace challenges and embrace failure as a learning opportunity.
To maintain your progress and avoid relapse, use the "four laws of behavior change" (identify the cue, have a plan, make it attractive, make it easy) to solidify your new habits.  
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