Simply allow oneself to awake naturally in the morning.
Rationale The natural sleep wake rhythms of the body varies according to the season and latitude. Awakening according to an alarm clock independent of human rhythms may seem 'efficient' but it stresses the sympathetico-adrenal system. Of course many people stay up late at night because they are unnaturally stimulating the body with alcohol, bright lights, television, etc.. Natural awakening will influence natural going to sleep also.
Source: James L Wilson, MD