This concept was popularized by the mindset coach Todd Herman who worked with Kobe Bryant to develop his “black mamba” persona — so called alter ego.

This process is creating either a fictional identity that embodies the strengths and virtues you wish to bring to a situation or evoking the image of a real person or figure who embodies these qualities in their identity. You then “step into” this identity every time you enter whatever your “field of play” is. The field of play is the context in which you wish to draw on this “alter ego” — sales calls, athletic events, business planning, coaching, etc.

Another prominent real life example comes from the singer Beyonce. She has an alter ego she takes to the stage known as “Sasha Fierce” which is meant to embody the elements of confidence, power, and tenacity she wishes to bring to her performance.

A couple fictional examples may be Mike the always-on CEO who struggles to unplug and relax with family. So he creates an “alter ego” called Zen Mike. When he gets home at 6pm he steps into this identity which is all about presence, peace, and caring. Sara is a mom raising two kids but she just got promoted to VP of Sales. So she chooses Wonder Woman as her persona every time she enters the boardroom or an important sales meeting. This persona represents poise, certainty, and courage.

There are many examples but the process is roughly the same.

1. Identify your field of play. In what contexts will you use this identity?
2. Identify your enemy. What is the tendency or pattern or default setting that gets in your way? Is it negative self talk, doubt, laziness, fear, confusion, etc?
3. Identify your desired traits and/or alter ego. What are the qualities, capabilities, and actions you wish to take? What or who would embody that?
4. Activate with a “totem” and/or ritual. This is an important step not to overlook. You need a certain trigger to get into that state. This should be something physical like an outfit or object. And it will likely include some small ritual: a song, a moment of reflection, an affirmation, a movement, etc.

Reference — You may find this study bolsters this general line of thinking. They asked children to impersonate Batman while completing a difficult task and it made them more poised, adaptable, and resilient.

White RE, Prager EO, Schaefer C, Kross E, Duckworth AL, Carlson SM. The "Batman Effect": Improving Perseverance in Young Children. Child Dev. 2017 Sep;88(5):1563-1571. doi: 10.1111/cdev.12695. Epub 2016 Dec 16. PMID: 27982409.