Pulled shots come from a closed clubface or the path swing, most players suffer from the latter as they start their downswing with their shoulders causing their path to go to the left
Too many players worry about mechanical and technical things throughout their swing and never focus on balance which is the key to a stable shot, see if you are in balance by trying to hold your finish position until your ball lands
Hitting the ball fat tends to come from either falling backward on your backswing or overusing your hands and uncocking your wrists too early