When I do all nighters, I reset my caffeine tolerance and drink a soda in the early morning when I need it. The next day I take a cold shower, have more caffeine, and intermittently work out just enough to keep me awake. After the second noon it's usually easier. I never skipped two nights in a row though so I don't know how hard it'll get. Maybe try caffeinated milkshakes for the second day?