[play] by {one's} own rules

to do things as one sees fit, not according to laws or rules

Despite the company guidelines, she preferred to play by her own rules when managing her team.
As an independent artist, he decided to play by his own rules, ignoring the traditional pathways to success.
The innovative entrepreneur built his startup by playing by his own rules, defying industry norms.
In the world of high-stakes poker, he was known for playing by his own rules, often surprising his opponents.
She found success in the fashion industry by playing by her own rules and setting unique trends.