api versioning: when and how to implement it

Hey everyone, I've been thinking a lot about API versioning lately, especially as our services grow and evolve. When do you guys find it's the right time to introduce versioning to your APIs? Are you typically doing it from day one, or waiting until a breaking change is imminent? I'm also curious about your preferred strategies. Do you go with URL path versioning (like /v1/users), query parameters, or custom headers? What are the pros and cons you've experienced with each?