Ring around the collar is caused by the build up of body oils and sweat around the inside of a shirt's collar. To remove a ring around the collar stain, you need a heavy-duty detergent such as Tide or Wisk, a toothbrush, baking soda, hydrogen peroxide and water.
Gather your materials
Grab your shirt and your laundry detergent. Gather your cleaning agents.
Pretreat the stain
Pour a thin strip of Tide or Wisk over the top of the stain. Scrub the inside of your collar with an old toothbrush. Let the detergent sit on your shirt's collar for 10 minutes.
Wash your shirt
Wash your shirt in warm water with a regular amount of Tide or Wisk.
Treat the remaining stain
Treat any staining that remains after washing. Mix 1/4 cup water, 1/4 cup hydrogen peroxide and 1/4 cup baking soda. Pour the mixture over the stain, and scrub with a toothbrush. Let the shirt sit for 30 minutes.
Wash the shirt again
Wash the shirt in your washing machine again. Use Tide or Wisk and the warm or cold water setting on your machine. Inspect the collar of the shirt when the wash cycle is complete. Repeat the water, hydrogen peroxide and baking soda treatment if any stain remains, and wash the shirt for a third time.