Some weeks ago, a friend sent me a the link to a YouTube video of a monk dying consciously. It demonstrates the sublime art of spiritual living and leaving. You might be interested in the text on “Dying and Deathlessness” (with info about help during dying; see the text as PDF here) or about “Death, Birth and Continuity” (PDF here) . In the book “Enlightening Encounters” (p. 31ff) of Dr K. Parvathi Kumar you find the profound story of Sreeman Ekkirala Ananthacharya, the father of Master EK, who also departed in a yogic posture and with full consciousness -which is rare in the present times.
Just lying down and departing, then the body carried away by the other monks (picture from the video)