In order not to spray polish or compound all around, start out by setting the buffer speed to the slowest setting.
Begin slowly and move the buffer over a small area (about 2 feet by 2 feet) until the area is covered with polish or compound.
Gradually increase the speed while moving the buffer over the area. Start horizontally, being sure to go over the entire area. Go back over the area, in vertical passes, to ensure the entire area is buffed. When the area starts to look shiny, increase the speed setting to high and go over the area again, with light pressure, to finish.
It's best to end with a clean cotton cloth, terrycloth towel, or microfiber cloth to remove any dust and leftover polish or compound.
When using heavy cutting compounds, use caution—apply light pressure, and don't stay in one spot or you'll burn through the gelcoat or paint.