The 41-year-old musician is known for his laidback style and the Grammy-winner has admitted he never takes his wardrobe choices too seriously, because he feels fashion should be a journey of mistakes until you find the right look that works.
Writing in the February issue of GQ magazine, Mayer wrote: "You shouldn't let fashion hurt your feelings. If it does, that's a good indicator you're taking it way too seriously. Anybody, at any time, should be allowed to wear whatever they like. Whether it works or not will be for their future self to make peace with.
"God knows I have a very well-documented history of attempts. Take a hat, for example. Do you know how many hats you have to wear before you find the one that actually works? Wearing bad hats is the only path to a good hat. I'm still trying to fail. I'd like to lose on an outfit one out of every ten times. Means I'm trying. Or I'm not. Did you see how my point just crumbled before me? That's what happens when you try to apply too much thought to fashion."
John - who has recently teamed up with Ryan Adams to work on his album 'Big Colors' - also confessed that he loves his robes because they have multiple uses.
He added: "Everyone scratches their head about my wearing a robe until they try mine on. Then they understand completely. It's a jacket, but it's more laid-back. It's a tent you can hang out inside of as you go about your day.
"It's a security blanket of sorts. I still haven't explained it perfectly, because I can't. You just have to try one on that fits you right. Then you want it to take through your day like a companion."