Yeah, you think that'd be simple: sleep!
Here's the deal, though: I worked a 12 hr shift last night (8pm yesterday 'til 8am today). It's 09h30am now. As a favour to a co-worker (and a bit of overtime), I'm working at from 3pm 'til 8pm today. Chances are I won't be able to sleep 'til 11am at the earliest, and then have to get up 3 hours later to get ready to go back to work.
Should I snag the three hours or hold out 'til when I get home tonight at around 8:30pm to crash?
Did any of that even make sense...?