Taken from Brandon @ Myspace

I've been shooting alot on green screen lately, and rather cheaply too... I stole an idea from one of bosses while working in commercials and it works PERFECTLY...

Head down to your local fabric district (if your town has one) and buy bright green spandex. Using a PVC pipe frame or a frame from a projection screen and some Pony Clips, stretch the fabric across the frame... If you do it right, there'll be no wrinkles, and you'll have the perfect backdrop.

As for lighting, I essentially dumb down the big budget process of lighting... On most flicks I've PA'ed for, they light the green screens from in front and above, then light the actors later... So, if you have enough room, light up your green screen evenly (work lights with diffusers work well if you can kill the hot spots), then place your actors far enough in front of the screen, as well as the lamps lighting the screen, so that you can light them separately without the light spilling onto your backdrop...