How do i get out a yellow stain on cotton white skirt?

I would take it to a dry cleaner if you really want to keep the skirt, they have products that will remove just about anything. The problem with at home remedy's is the often wind up leaving a bigger mess than what you started with.

Try lemon juice and salt rubbed into the stain and then let it sit in the sun for a few hours. Rinse well and launder as usual.

bleach that skirt