Yoga Nidra is a form of deep relaxation, and could also be called a form of meditation. In a Nidra practice, we explore different states of consciousness, surfing the interface between waking and sleeping to find the hypnagogic state. It is typically practiced laying down in Shavasana, and can do wonders for the parasympathetic (rest + digest, restorative) nervous system.
Find yourself a calm space, and make yourself as comfy as possible - blankets, bolsters & cushions are all welcome.