I will make a plea here for orthodoxy and tradition.
Make sure your foot spot is placed perfectly and correctly.
Outline the outside of the rack you will always use.
Line up the rack with the best measuring tools you have (squares, rulers, laser, etc.)
Draw the line with PENCIL (not too sharp, but not extremely dull) so it is less intrusive and noticeable while you are shooting, but easily noticeable when you need to assess the position of a potential break shot. Trace the outside of the rack while it is in position, being careful to not move it until all 3 sides and the corners are complete.
Draw a straight line in PENCIL from the center of the spot to just below the center diamond on the foot rail; also in pencil; to help with spotting balls during the game.
This is the way Willie Mosconi insisted a friend's table be set up; it is good enough for Betmore's Basement; I would tolerate no other way (when a professional friend insisted that I re-do my lines with Sharpie, I complied, but hated it so much I changed the cloth).