Look for players who are sloppy dribblers, or who expose the ball when they pick it up. Someone who doesn’t seem to have a very tight grip on the ball as he prepares to pass -- especially if he’s holding the ball away from his body -- could be a suitable target if you’re fast enough. Loose dribblers who don’t keep that ball under control might be unwittingly offering you extra time to snatch the basketball away mid-dribble.
Watch players to see how their bodies move before they make certain plays. Some players telegraph what they're about to do. For example, if someone is about to turn to the right and throw the ball to a teammate, she might keep her arms still but turn her shoulders a bit. She’s attempting to fake you out by leaving her arms still, but her body is giving out clues that she’s going to turn. Looking at the player’s torso and shoulders can help you spot such moves.
Act a bit lazy yourself as you zero in on a ball you want to steal. In a January 2014 article on top defenders in college basketball, players told "Sports Illustrated" that they try to seem like they’re “off-guard” or “resting,” when in fact they’re watching the ball and waiting for a moment to strike. These tactics can make the player with the ball assume you’re not much of a threat, and he might be less likely to protect the ball carefully.
Keep an eye on where nearby offensive players are standing. You might have an opportunity to intercept a pass. If the player holding the ball decides you aren't looking and throws the ball to another player nearby, you'll be in a better position to dart in front of the intended target. Instead of trying to snatch the ball out of the air from the side, be ready to place yourself in the path of the ball so you're the one who gets it.