For a non airbrush option, I chromed my helmet with Krylon Looking Glass High-Gloss Silver Reflective Finish Spray 6 oz
[URL unfurl="true"]https://www.krylon.com/en/products/craft/looking-glass-paint[/URL]
I would spray the chrome into the air and then swipe my visor through it, on the inside just like you. I repeated until it was reflective, but I could still see through it.
My example of my undyed, only spray painted, visor. With a fan going I can see out it just fine outside. In a dimly lit room, not as great.
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