Step 1: Decide who will be in front of the camera and record you clips. You will record three times. First recording is shot as the person in center - you will have two partners stand on either side outside of the shot on either side and read the lines, of Good Advice (GA) and Bad Advice (BA). This first shot is NOT in front of greenscreen. The GA and BA shorts ARE in front of greenscreeen. Then you'll shoot the as GA, with two partners standing out of camera on the right reading the lines. The third recording is shot as BA with two partners standing outside of shot camera left.
Step 2: Capture all clips into Vegas.
Step 3: Organize the three clips on your timeline.
Step 4: Use event pan/crop to size the GA & BA clips onto shoulder. Drop Chroma Keyer onto GA & BA clips.
Step 5: Insert Audio Pan onto GA & BA clips. Pan the GA sound to left speaker and BA to right speaker.
Step 6: Render and enjoy.