How? Consulting with your mirror every time you go out of your home. Checking your look from front, sides and back. Head to toe. Still and moving. Checking if everything is fine, flowing properly. If there isn’t anything missing like a button or if there isn’t anything weird going on. And if the whole look suits you and the occasion you are heading to.
And you can also consult with it when you try something new, at a store. Obviously. And always check front, sides and back. Head to toe. Still and moving.
If you do it and listen to it, then the mirror will be your best friend on that.