This checkpoint can be a little difficult to determine. This is why I have grabbed a badminton racquet with a small shaft extender on it. Now I understand you might not have one of these in your garage, but you may also want to use a tennis racquet or just a bandminton without an extension on it is great too. Swing back and check where the face of the racquet is pointing. In the picture you can see the whole face of the racquet: this is good. If the face of the racquet is pointing up or down you are changing the club face. Therefore on the downswing you will need some maneuvering of the club to get it back to square for good impact.
After you have confirmed a square club face try to focus on the feel in your arms, wrists and hands. If the clubface is not square at the top, first look at your wrists. Figure out good wrists and bad wrists. Using the big racquet will help you feel and see this position easier. After a little practice, go back to your club and check it out.