This might be intuitively obvious to normal people, but I'm apparently a little dense. Laying flat for somewhere between .5 and 24 hours is important. Drinking water is important. But no one mentioned that it is a very bad idea to bend over a few hours after the LP. Of course, you would say, DUH! But I just figured if I was able to get up after 2 hours with no headache I must have dodged the bullet. I was wrong. SOOOO, my final contribution to LP advice is, if you need something that is on the floor, wait for someone else to pick it up. Call a friend. Leave it there. If you absolutely MUST pick it up, squat. But whatever you do, don't bend over!
(I did not bend over today, day 6, and did not have the headache!)