An even cheakier alternative is to mis-head the ball, so they don't connect properly. Normally deceives the keeper (if you're near enough) and the ball just bounces into the ground. I'm afraid I can't tell you how to do it though (I don't know myself).
Volleys are distinctly easier to hit into the ground than into the top corners, I find. Those swivel volleys from low crosses normally strike into the ground, don't they? To do those the ball needs to be at a reasonably low height, and when it's approaching press and hold square |¯| down from an earlier time.