Catch them doing it right!  Praise is much more likely to motivate us to do a task well than negative reinforcement.   If we work to “catch our children doing it right,” we not only motivate them to continue doing the task correctly but we enhance their self image.  When you catch a child doing it right, make sure your comments are sincere and specific!  Instead of saying, “Good job!” say,”Good job!   I like the way you organized your toys on the shelf.”  With patient repetition, you’ll be enjoying the results of encouraging the desired behavior.