E-tech rear tint spray - laquer or not?

[Andymac]

As title, I just got some e-tech lens tint spray, shall I follow directions on the can or shall I key the lights with sandpaper first? The can just says wash first then spray then apply another coat if needed and thats it?

Also would you laquer after or not? I like it to look gloss as the car shines up well so it will look good

thanks,

Andy