I work 11p-7a, anywhere from 24-28 hours a week, and I'm in nursing school
full-time during the day. So I'm always flip flopping between day sleep and night sleep, but there is NO way I could stay up all night on the nights I'm not working, especially with school in the morning.
I work Tuesday nights and Friday nights, and every other weekend. So when I work on my weekend, I get into a nice little routine of day sleep, since I'm working 3 nights in a row. I like to sleep almost as soon as I get home.. I usually end up passing out between 730 and 8 am.. it's just what works for me. I am always exhausted by the time I get home. I end up sleeping until about 3 or 4 pm, so I have my whole evening free until it's time to go back into work again. I find that if I get any less than 7 hours of sleep during the day, I'm so exhausted and it feels like I didn't sleep at all. I slept from 730a-430p today after work, and I woke up really rested.
It sucks flip-flopping right now, but for the most part it works.. plus the extra differential for working nights is nice.
You will find what sleep schedule works for you. Some of my co-workers like to split up their sleep, and sleep a few hours when they get home, and a few hours before going into work. For me, it works better to sleep a good 7-8 hours during as soon as I get home. If I didn't get much sleep during the day, I find it helps a LOT to even take just a 1 hour nap before work.. it really makes a difference.
Oh and drink a ton of water during your night shift. It helps me stay awake.. I don't really drink caffiene for the most part.