You hold a black colour wand in your hand and try to do some magic. The magic
doesn’t happen since you need a red colour wand to do it. So you
pass your hand over the wand and presto, it changes into a red colour wand!
Since you don’t want the wand to do magic on it’s own – You pass
your hand over it one more time and it changes back into a black wand!
Even spin the wand to show that it is absolutely normal! This can be
repeated any number of times! Very visual and very easy to do.