Create a new file: 300 x 300, 16 million colors, 72 pixel resolution, white background

Create a new Raster Layer (Layers | New Raster Layer) named Glitter
Using the Text Tool
Text: I used Matisse ITC, 72 Point
Size: 48-72
Stroke Color: Null (the crossed out circle)
Fill Color: #C0C0FF
Both Texture Settings: Null
Floating & Antialias Checked

Drag text to the approximate center of the canvas
Save Selection to the alpha channel (Selections | Save to alpha channel)
Deselect

Add a new Raster Layer named Cutout
Load the Selection from the alpha channel (Selections | Load from alpha channel)

Apply the Cutout Effect (Effects | 3D Effects | Cutout)
Vertical: 2
Horizontal: 2
Opacity: 60%
Blur: 5
Do not deselect

Click on the Glitter Layer to make it the active layer

Add Noise
Effects | Noise | Add
Noise:
100 Uniform

Apply the Motion Blur Effect (Effects | Blur | Motion Blur)
Direction Angle: 90 degrees
Intensity: 12 pixels

Add Noise again (Effects | Noise | Add Noise):
100% Uniform

Change the Layer mode from Normal to Dissolve
Do not deselect

Create a new Raster Layer named Drop Shadow

Add a Drop Shadow
Effects | 3D Effects | Drop Shadow
Vertical: 4
Horizontal: 4
Opacity: 50 %
Blur: 6.2

At this point, you should have a multicolored glitter text.

You can alter the colors of the glitter (With the Glitter layer active):
Colors | Adjust | Hue/Saturation/Lightness

To keep the multicolored look, but alter the glitter colors, choose Master from the Edit list (make sure the Colorize box is UNchecked) and move the Saturation and Color sliders. The higher the Saturation number, the brighter the colors will be. The best thing you can do is experiment and see what happens.

To make the glitter monochromatic - check the Colorize box and experiment with the Saturation and Color sliders.

If you'd like the glitter lighter or darker, move the Lightness slider up (lighter) or down (darker).

Crop, save and you're done!