To build a better you, you need to start, without any action no change can occur.
Depending on what you wish to change, determines where to begin.
The first action to a better you is to believe in yourself, believing you can change and for the better is a great place to start your rebuild. Believing in yourself will provide endless possibilities in your life. Be thankful for your life, life is very short and no one knows when it will end.
Try and improve or do better than you did the day before. It maybe only a little improvement, but they will add up and develop into a better you. You want to live in a state of continuous improvement as this will form the building blocks of a better you.
Visualize what you want to achieve and you will be amazed how your life will develop. Your visualizations should be regular and what you really want.
Take action towards your goals, any action toward your goals is a step forward. Your actions may not always be successful, however every failure is a learning experience.