I work a lot of nights and have never really a lot of issue with it.. but then I've always been a night person.
Try to keep busy as much as possible. Obviously, do your job too but even if the only thing you can do is get up and walk around then do it. Assuming you're inside, get outside every once in a while to get that cool night air. It can really help if you're having trouble.
Water is great, as is eating. Obviously, don't scarf candy all night but keep snacks handy. Carrot/celery sticks, grapes, etc. Anything that's easy to munch on and will give you a shot of energy.
Another great use for (cold) water is to put some on the back of your neck or on your forehead. It's more of a shock to the system than anything else and won't really help you stay awake and alert, but if you know you're crashing and need to do something fast, it works wonders.
Sleeping during the days can be rough but it's really a pattern. Deciding whether to sleep as soon as you get home or to wait a bit and get better rested right before your next shift is up to you, but developing a regular routine is a good thing. Make sure where you're sleeping is as quiet and dark as possible (I know it's not always easy during the day, especially if you don't live alone) and just keep at it. Eventually your body will adjust itself, even if it takes a few days of almost no sleep for it to get the message.
Hope some of that helps.