Hang a plain white sheet or a dedicated projector screen flat against a wall or between two posts, since wrinkles or a light-colored patterned surface will distort the picture. Wait until it is fully dark before starting, since most projectors are too dim to show a clear image against daylight or twilight. Set the projector on a stable table or stand at a distance matched to your screen size, since projectors typically need several meters of throw distance for a large image and getting this wrong leaves the picture too small or spilling past the screen edges. Run a test with the actual movie for a minute before guests arrive to check focus, volume, and that the image is square on the screen, since fixing these issues in the dark with an audience waiting is much harder. Connect external speakers rather than relying on a projector's built-in speaker, since built-in speakers are usually too quiet for outdoor viewing where sound spreads out and background noise competes with it. Lay out blankets, cushions, or lawn chairs before dark so seating is settled before it gets hard to see, and have a plan for bugs, such as citronella candles or bug spray, since flying insects are drawn to the light from the screen.