Live In the Present
Take therefore no thought for the morrow: for the morrow shall take thought for the things of itself. Sufficient unto the day is the evil thereof.
Avoid living in the future. This manifests itself by constantly waiting for the right time to do something, or worrying about how the future will unfold. Right now is the time that you have been waiting for. The best way to prepare for tomorrow is to focus on today. Think about what you can do today, not what you should do in the future.
Conversely, avoid living in the past. Use the past as a learning experience. Reframe past mistakes as lessons: failure from risk is good, and failure teaches you more than success. Use the past as a learning experience.
Instead, live in the present. First, plan for the future by settings goals and developing a system to achieve those goals. Aim low but up. Break things down into smaller steps and start with small steps to build momentum. Learn from past mistakes and incorporate these valuable lessons into your plan. Then, focus on the present and live in day-tight compartments. This helps to mitigate worry about the future. You have captured the future as an aim to work towards and planned for the future - now live in the present.
Shut the iron doors on the past and the future. Live in Day-tight Compartments.
You don't want to live only in the present and ignore the future, and you certainly don't want to ignore the valuable lessons you may have learned in the past. Have an aim, and then focus on the present day. The day manifests itself as challenges and problems, and as you solve them properly, you stay on the path towards your upward aim. By first having an upwards aim in the far distance, you can concentrate and live in day, knowing that what you are doing is in service of that aim. This makes every moment in the day meaningful in a way that sustains your life.
References
12 Rules for Life by Jordan Peterson
How to Focus by Thich Nhat Hanh
How to Stop Worrying and Start Living by Dale Carnegie
The Almanack Of Naval Ravikant