In this tutorial, we will draw the neuroanatomy of the flip-flop switch. Key structures: hypothalamus, ventrolateral and median preoptic hypothalamus, lateral hypothalamus, orexin, pedunculopontine nucleus, lateral dorsal tegmental nucleus, locus coeruleus, raphe nucleus, substantia nigra, ventral tegmental area, basal forebrain, tuberomammillary nucleus, ventrolateral periaqueductal gray.