What you need to do to stay awake is basically this: not watch tv and not eat anything. The latter unfortunately doesn't help you focus, though.

Watching tv numbs your brain in an entirely unacceptable fashion. Especially in combination with food, before a long session of final studying. What to do? Nap? Coffee? I actually bought tea instead of coffee this morning... 20-30 minute nap? If it helps it's a blessing, but sometimes it does the complete opposite. But I have been awake since 6.00 so... a wee slumber?