The use of alignment rods along your foot line and target line can be very beneficial when practicing.
Another great way to work on your alignment is to use an alignment rod along your target line while out on the golf course. If you get a chance to practice on the course this can be very beneficial.
The best way to work on your alignment is away from the golf course. Do some mirror work for your address position face on and down the line.
Face on; check for hand position, stance width and ball position.
Down the line; check for proper spine angle, distance from club and shoulder position.
Most people can get their feet parallel to the target line, but struggle getting their shoulders parallel to the target line. It gets even more difficult as ball position moves forward in the stance with longer clubs.
Stand in front of a mirror with a down the line view. Get into your setup position, when you rotate your head to look back into the mirror you should be able to see a sliver of your front shoulder. If you see all of your front shoulder you are to closed at address and if you see none of your front shoulder you are to open at address.
Mirror work is a great way to improve proper alignment.