If your shots are constantly fading or slicing then your clubface must be aiding in getting the ball to curve this way. The most important factor in determining the clubface angle is the grip and if you're a slicer/fader then there is a very good chance your grip is weak - no matter how it "feels"! A weak grip leads to active/flippy hands through the hit and this takes away from a golfers ability to trap or compress the golf ball. You know the feel and sound when you hit one just right....that's what we're after!
As you grip the club in your normal fashion rotate the face down/closed from vertical 30 degrees and then set up to the ball. Keep in mind that 30 degrees is equivalent to one hour on a clock so don't over do this. Be sure that all you have changed is the club position. Now the face will feel very closed at address, and you need to work towards getting (and keeping) the face square at address without altering your grip.