How do you clean ring around the collar?

About.com explains that ring around the collar requires a pre-treatment with a solvent-based stain removal product, such as Shout or Spray 'n Wash, because the stain is a combination of body oil and daily soil. About.com also mentions stain sticks work well. For people who do not have a solvent-based stain remover, About.com suggests applying a heavy-duty liquid detergent to the stain and working it in by gently rubbing.