For goodness' sake! Try to look the part.
Would you buy a suit from someone who looks and acts like they’ve never worn one? If it’s cheap enough, perhaps…
It’s not enough in this world simply to know your stuff. If you want a chance to prove it, you need to look the part. Because the facts are that people do judge books by their covers, and covers do say quite a bit about books’ content.
Besides, it’s hard to trust someone who won’t take their own advice, use their own product or eat their own dog food.