Fake it till you make it

"Fake it till you make it" (or "Fake it until you make it") is an English aphorism which suggests that by imitating confidence, competence, and an optimistic mindset, a person can realize those qualities in their real life and achieve the results they seek.
The phrase is first attested some time before 1973. The earliest direct reference is a Simon & Garfunkel song "Fakin' It" released in 1968 as a single and also on their BOOKENDS album. There Simon sings "And I know I'm fakin' it, I'm not really makin' it."
Similar advice has been offered by a variety of writers over time:
In the Law of attraction movement, "act as if you already have it", or simply "act as if", is a central concept:
In the 1920s, Alfred Adler developed a therapeutic technique that he called "acting as if". This strategy gave his clients an opportunity to practice alternatives to dysfunctional behaviors. Adler's method is still used today and is often described as "role play".