Need help re black out headlights re lenses

[Chromey]

My question is and I have tried to search, is how do you get the lens to look black? I assume you obviously don’t paint them.. How do Oss etc do it. Or am I mistaken and when you paint all black they just look black ?

[Redd]

The surrounds are painted, the lenses themselves are clear. This is enough to make the headlight look 'black'.

[Chromey]

cheers makes sense Wasnt sure