Backyard paint booth

The clean work area mentioned by several above is imperative. It's also a good idea to check the condition of hoses and such.

Here's an anecdote:
Years ago, I did mechanic work for a small local shop. The owner did bodywork in another building. He was putting the final touches on a beautiful '57 Chevy when it happened. He'd shot the second coat on probably 90% of the car when a hose broke about 8 feet from the connection at the wall. He had 8 feet of hose flailing around and finding lots of dust that his broom had missed (in theory, the dust wouldn't have been a problem under normal conditions) while banging against the freshly-painted hood and fenders. Oops. It's also a good idea to refrain from driving over hoses used for paint.

A few hours later, he pulled me off of a nightmare clutch job (another '57 with the original 3-speed driveshaft behind a T-10... grrr) because he had to go chase parts and the other one had to be scuffed down for a repaint. He chased a lot of parts when something unpleasant had to be done.