Find a flat, non-busy(!) parking lot. Use two consecutive parking spaces as the "court". Use the middle line as the "net". Put a cone or t-shirt on the open "side line" (where the car would enter the lane).
Play one vs. one (or two vs two). One player has one lane and the other player has the second lane. The server lets the ball bounce one time (or volleys out of the air) and volleys the ball over the net. The second player has one bounce (if he/she needs it) and up to three touches on the ball to get the ball back over the net, using any part of your body except your hands. The one bounce does not have to come before the touches (i.e. you can chest the ball down, let it bounce once, then juggle once and hit the ball back over the "net").
Continue until one player uses too many touches, too many bounces, or can't return the ball back onto the other side in play. All lines are considered in play (including the center line). For beginners or for getting used to the game, loosen the restrictions to two bounces and five touches. Play to 15 and alternate who serves with each point. Get a group together and have a mini-tournament! The game will improve your first touch, volleys, and headers.