earn (one's) stripes

To prove that one is deserving of a particular position or designation. I told the recruiter that I earned my stripes as a teacher before moving into administration.

Gain a position through hard work and accumulated experience. For example, She'd earned her stripes by serving for years as the governor's secretary and personal aide . This expression alludes to a military promotion or award, indicated by strips of chevron or braid added to the recipient's uniform and known as stripes since the early 1800s.

If you earn your stripes, you gain enough experience to deserve a particular job or position. Mr. Thaddeus earned his stripes playing for such foreign bands as the London-based Pitiful Souls and Singapore's X-Periments. He has worked hard to earn his stripes as a skilled debater in the House of Assembly.

To gain a position through hard work and the accumulation of experience, often in the face of difficulties.