Magicians use distraction techniques to draw the audience’s attention away from whichever hand is engaged in sleight of hand. Magicians can accomplish this by encouraging the audience to look elsewhere or by having an assistant do or say something to draw the audience’s attention away. Sleight of hand is often used in close-up magic, performed with the audience close to the magician, usually within three or four meters, possibly in physical contact. It often makes use of everyday items as props, such as cards and coins. The guiding principle of sleight-of-hand, articulated by legendary close-up magician Dai Vernon, is “be natural”. A well-performed sleight looks like an ordinary, natural and completely innocent gesture, change in hand-position or body posture.
It is commonly believed that sleight of hand works because “the hand is quicker than the eye” but this is usually not the case. In addition to manual dexterity, sleight of hand depends on the use of psychology, timing, misdirection, and natural choreography in accomplishing a magical effect. Misdirection is perhaps the most important component of the art of sleight of hand. The magician choreographs his actions so that all spectators are likely to look where he or she wants them to. More importantly, they do not look where the performer does not wish them to look. Two types of misdirection are timing and movement. Timing is simple: by allowing a small amount of time to pass after an action, events are skewed in the viewer’s mind. Movement is a little more complicated. A phrase often used is “A larger action covers a smaller action”. Care must be taken however to not make the larger action so big that it becomes suspicious. https://en.wikipedia.org/wiki/Distraction