Catching the ball

I've been playing GK for a while everytime I play 7vs7 with a group of friends and have been trying to improve on the role ever since. One of the big mistakes that I can't seem to ever really fix is that I find difficult to stop the ball with my hands. Regardless if the shot comes low, high or right at my chest, I always hit away the ball instead of stopping it, even when it should be very possible to do so. Do you have any tip to give for me to work on?