They are super easy to make. . . basically you get a water tight bottle or jar of some sort, pour in about half a bottle of Elmer's glitter glue -OR- Elmer's clear gel glue and your own glitter. I prefer this method, as clear gel glue and glitter are cheaper than glitter glue, and then you can mix colors, and add as much glitter as you want (the more the better in my opinion!) Then you fill your jar almost to the top (leave room to shake) with warm water. I also add a few drops of food coloring just to make the water more fun when the glitter is all settled. Then glue the top onto the container and shake like your life depends on it.
I also composed this little poem to explain how to use the glitter jar which I will attach with a ribbon to make it more "gifty." Feel free to use this poem on your own glitter jar gifts!