Summarize:

A short nap will help you feel energized for a long night. Try to avoid napping for more than two hours or you might end up feeling lethargic and tired. Quick naps will be more likely to refresh you. Power naps can be a good way to recharge yourself in the mid-afternoon before you stay up late. Find a comfortable place and lay down. You can even lay your head down on your arms if there is no place to go horizontal. Set an alarm for thirty minutes later, put on some soothing sounds from the internet, and you'll wake up feeling refreshed. If you are already overtired from not sleeping the past few days it will be much harder to stay awake. Try sleeping in the two days before you know you're going to need to stay up very late. This also depends on what you'll be doing the night that you stay up late. If you have to stay up late to do physical labor like construction, a lack of sleep may not impact you that much. Generally, as long as you haven't been sleep deprived for a long period of time, your heart and lungs and muscles can operate equally well. It's your brain and cognitive functions that struggle on a lack of sleep. If you know you're going to need to think clearly and quickly the night that you stay up late then sleep will be very important. Heavy meals will cause you to feel sleepy as your body tries to digest what you have just eaten. Avoid heavy carbs and stick to lean meat and fruit if you are planning on staying up very late. Protein will help you stay up later because it stimulates the neurotransmitter orexin. Orexin boosts wakefulness, so eating a steak could be a good way to stay awake. Don't gorge yourself to the extent that you have an incredibly full stomach. Digestion will make you sleepy. Just snack on bites of steak or another lean meat.
Take a nap ahead of time. Sleep late the night before, and the night before that. Avoid heavy meals.