Here’s a blog post by Bill McKibben:
Rules for Sleeping on the Bus
1) Feet go toward the front of the bus. So if something happens and Jim slams on the brakes, it’s your feet that take the hurt
2) The farther back in the bus, the higher you bounce with each bump
3) It’s very womblike when the bus is rumbling down the highway—the constant throaty vibration lulls you beautifully
4) But when the bus stops, and the engine turns off, you wake right up. The new city is disorienting—you went to sleep in Omaha and now you’re in Denver. But it’s okay. The bus is the bus is the bus, all across America.