Infield - Ground Balls
Unless the ball is absolutely ripped at you and you don't have time, get in the habit of moving toward the grounder as you prepare to field it. Notice the word 'charge' wasn't used -- that word implies running towards it as fast as you can. Unless it's a slow roller, you want to approach the ball in a controlled manner that is aggressive but not out of control. This allows you to make adjustments so you're not catching it off a short hop or taking it off the first bounce on the infield dirt. As you get closer to the ball, begin breaking down to get into position to field the ball. To do this, shorten your steps and widen your feet. Bend not only at the knees but also with your back. Put your hands out in front of your body and open your glove toward the ball with your bare hand on top.
There are a few common problems that players make when catching a ground ball.
In all situations, try to avoid catching the ball on a short hop. In the diagram below, the approximate area of the short hop is shown in red. Catching the ball on a short hop is a difficult play to make. It takes practice for players to get in good position to avoid fielding a short hop.

The backhand play is one of the most difficult to make. Poor technique and lack of practice are two of the biggest reasons why players struggle with the backhand play.
As you approach the ball you will either field it with your left foot forward or right foot forward depending on when you get to it. Many players will practice fielding a backhand only one way, but the fact is you will have to make the play both ways so make sure you practice both ways of fielding a backhand. Either way you want to make sure you keep your glove in front of your face. You want to watch the ball all the way into the glove.