Bottles & Jars
You can use pretty much any clear bottle or jar, but you will want to make sure it has a lid that seals. Once you get your bottle filled, use hot glue to seal it so nothing comes out.
Pretty much any food coloring will do, but I will say it's easier to make colors like purple without having to mix them yourself.
You'll want to use a clear glue when making glitter bottles. That way the liqued doesn't get cloudy, and you can see your glitter sparkle at its best!
Probably my favorite ingrediant, (if you haven't guessed by now) is glitter. You can get various sizes of glitter, but I like to use 1/250" glitter, often labed "Ultra Fine" or "Micro Fine". You can also find fun things like glow-in-the-dark glitter, pictured in the center.
The most expensive thing on this list, no doubt, is luster dust. Luckily a little goes a long way. You're probably best off buying this off of Amazon, as a lot of craft stores don't cary it. Technically, it's fine enough to be considered edible, and is used in things like drinks, or cake decorating. I've had some people say they've had success using other pigment powders, but this is one that I know works for me.