The key is to apply active listening techniques in your everyday interactions. You won’t have a button to push when you become distracted by your mind, but you can say 'I’m not listening' to yourself. Then, let that thought go and calmly refocus on what the person is saying.
It may be helpful to summarise what they’ve said back to them, which shows that you were listening and gives them the opportunity to point out anything you’ve misheard or misunderstood.