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Hold the tip of your mitt against the ground. Follow the ball as you attack it. If the ball takes a hard bounce, you can move your glove up to stop it. Keep your glove at an incline and use the heal of your wrist to stop the ball. Practice this by having someone roll or hit some balls directly at you. When the mitt is held flat on the ground, balls can roll up your arm. When the glove is held straight off the ground, it'll block balls rather than catch them. Shortstops need to be mobile. Anticipating balls and getting to them quickly is crucial. Practice shuffling to the side to get to balls not hit right at you. Hold your glove down and use your feet to get yourself into position. Add a small hop to your routine. As soon as the bat hits the ball, hop so you can get your feet moving. Catching balls in the center of your body should only be done if you don't have time to move. Keep your arm near your side. Align your arm and mitt with the ball's path after getting into position. This prevents your muscles from tensing, so you'll make less errors. Even when a ball is hit to your opposite side, you won't cross over yourself. You'll plant your back leg ahead of you and make a backhanded catch. Once the ball is in your glove, pull your arm up into your chest. This secures the ball and readies it for a throw. Rushing means you try to transition the ball to a throw before you've secured it, so it pops out of your glove. When the ball is centered, your body will feel balanced so you'll be less likely to make an errant throw. When a ball is hit hard, you won't have time to get into position. You should anticipate where the ball will go and step towards it. Plant your dominant foot ahead of you. Aim to have the ball land between your thumb and pointer finger, then push your glove against the ball to catch it. Moving too early for a ball gives the batter an indication of what pitch is coming. Instead, stay in place. Watch the pitcher deliver the ball. When the batter is about to swing, move to where you need to be. Keep the batter guessing so he doesn't get a hit.
Keep your mitt low to field ground balls. Work on your footwork. Field balls on the mitt side of your body. Bring fielded balls up your chest. Backhand catch balls you can't get in front of. Pay attention to the pitcher to avoid tipping off the batter.