If an interviewer asks a person the methods adapted or taken by the person to improve him or her what are the methods that can be given and also followed?

Not only for answering but even for following one of the best method a person can adapt for improving is to do defect analysis and change management practice. That is defect analysis means that analyzing the root cause or the approach for defect or failure and change management practice is the further steps taken by one in order to prevent the defect.