Set up two hula hoops about a foot apart on your swing plane angle and then swing through the gap between them
One of the most common faults in the swing is taking the club back outside, to fix this many players try to control the clubhead but in the swing it is actually the club handle that controls the clubhead so put a tee in your grip and measure your handle distance from your body through the swing
Open your clubface, aim left and swing outside in