Originally Posted by BlazingPedals

When i have to take the rear wheel off while on a ride, I first loosen the Q/R skewer, then stand on the non-drive side and lift the rear end off the ground. With one hand, I pull the derailleur cage back, which releases the wheel to drop out of the dropouts. I set the wheel aside and then lie the bike on its side, preferably in grass. After working on the tire/wheel, I reverse the procedure. Wrap the chain on the correct sprocket to match the gear indicator on the shifter, and pull the derailler cage back. The wheel falls into the dropouts with only a little bit of extra guidance. I've found that sometimes it's easier to install the wheel if the skewer is completely removed. (Don't lose parts!) As the final step, lift the rear end off the ground using just the ends of the skewer to make sure the wheel is firmly seated where it belongs, then flip the lever closed.

At no time would having the bike upside-down be an advantage.