Do not emit light yourself. You can glow, but only with radiance borrowed from elsewhere.
Take corporeal form. Acquire inertial mass.
Become at least partially diurnal, or failing that, inhabit a city that never sleeps.
Contrary to popular belief, it is not necessary to have a soul in order to have a shadow.
Maintain proximity with another body or surface, e.g. the ground, if you want visual evidence of your shadow.
Do not subsist mainly or entirely on a diet of blood.
If your shadow becomes inky, or disappears into Stygian darkness, you may need to dispense with the fedora and trenchcoat.
If you’re new to shadow-casting, work on getting a crisp, dark umbra before advancing to a penumbra and—for advanced students only—an antumbra.
To make your shadow dance, dance. To make your shadow talk, stand on a streambank.
Learn from your shadow. Broken glass won’t cut it, barbed wire can’t stop it, mud doesn’t stick.
Whether or not you have a dark side, you can do your part to keep the world from becoming a desert, blasted by the implacable light of reason.
At noon on the equator, your shadow will stretch into the earth like a vein of pyrite.
If your shadow is crossed by the shadow of a black cat, throw pepper over your shoulder.
Keep your friends close and your shadow closer.
Do not attempt to make love to your shadow. That’s been shown to cause amnesia in laboratory rats.
Don’t share your shadow with strangers. Ideally, everyone should cast his or her own.
If you see nothing, say nothing. The shadow government appreciates your cooperation.