Is this really something that babies will sort out on their own, or does anyone have any tips to encourage my baby along? She is very young so I don't expect her to have a routine, and the "sleep when baby sleeps" doesn't always work. I do keep the room quiet and dark at night, but she is bright eyed and bushy tailed until the sun comes up!
Re: Day/night reversal
Nursing a newborn at least every 2-3 hours and on demand also helps them sleep! Melatonin is the hormone responsible for regulating sleep cycles, and babies get this most readily from their mother's milk in the form of tryptophan, so frequent night nursing (during which time the levels in your milk will be higher) actually provides newborns the melatonin they need to sleep better naturally.
Good work, mama!
Don't worry that she's not getting melatonin from breastmilk (I shouldn't have assumed you were breastfeeding. I'm sorry). She will produce her own melatonin, and most babies begin regular production of melatonin between 9 and 12 weeks. Since darkness signals the production of melatonin, keeping the bedroom as dark as possible during the night, and following cyprissa's suggestions for a sleep-filled environment, should help.