It's probably counterintuitive to answer a personal question with a formula, and most interviewers will see through it, but a formula can help you structure your answer when you're preparing for the interview. Here's what career site The Job Network suggests:
...choose a weakness that you've since worked hard to convert into a strength. Formula for the latter: "Well, I was noticing that I was x, so I took , so I took step y in order to improve, and ended up in situation z (which is infinitely better and makes you a stronger candidate for the job)."
There are three factors here: the problem, what you did to overcome it and the result. This way, you're not shirking the question completely, but you are letting the interviewer know you have the ability to overcome this weakness, so it's not a problem. Again, it's less about following the formula word for word and more about structuring your own answer in a way that solves a problem.
For more advice on answering tough interview questions check out the full post for yourself at the link below.
How to Answer Tough Interview Questions in 60 Seconds [The Job Network]