Welcome to the Glitterbombing Business
I do not think that there is a strict answer to which colours are best. I personally always carry a black and a red permanent marker, since these are the colours I connect the most to Ellis. Silver/Metallic and Gold also seem like good ideas to me -- the "Lead to Gold" symbolism is very striking. The worthless lead of consensus reality being transformed to the Gold of Khaos and lives worth living by the Alchemy of Glitterbombing.
As for drawing it on your own stuff... I personally do not have it on anything that can be seen as mine. There are not many Glitterbombers, right? So, if someone sees a tag on a wall or anywhere, and then sees it on your stuff, he'll guess that is is your work. Now, he has no proof. But you are the primary suspect and graffiti is of course not exactly permitted officially. This is why I only have it on personal stuff that I
don't have with me in public.
If you are not worried about that and someone asks you about that sign on your bottle... you'll have to give an answer, hm? Most likely I'd say "Solve the Riddle" or "Seek the Secret"

These also make for good quick writings next to LS tags, I think. If you tag an LS with a line such a those and the Letters DKMU somewhere, folks might look it up on google and have their minds blown, which is of course part of the point, right

?
But let's be honest, in modern society you do not want
all random people around you (in your class/university, at your workplace and so on) to know that you personally are an occultist, or? And since the LS directly links to DKMU and that directly links to Magick... I would not draw it on things that link to me directly, i.e. my personal stuff, and I would not explain to peope what it means if they see a tag somewhere and (for some reason) ask me about it (unless those people are good friends, obviously).
This is just my personal opinion however, you can do it in any way you like. Obviously, it is always a good idea to try to find out/feel what Ellis thinks about your Glitterbombing.