I try to visualize the shape of the pitch and also the target. Then I focus on the smallest part of the mitt or catcher's body that I can and start my delivery locked on that spot mentally. I still think focused bullpens where you throw the same pitch to the same location for 5-10 repetitions helps me groove my delivery and my feel for that specific pitch. If throwing to a net, I set up a batting tee in front of it. I set it to the location I want to hit and place the ball on the tee. If I manage to knock it off, I've located exceptionally well.