How can i get marker out of my white couch?

Nurses often use plain medicinal alcohol (from a drugstore) to remove ink from white poly-cotton uniforms. Always test a small spot first. Remember that medicinal alcohol will appear to "spread" ink so use a small amount at first to a small stain, then dab with more alcohol as needed. It is best to apply alcohol to white rag (old washcloth if possible) rather than pour it from the bottle. You could also apply using Q-tips or cotton balls; use clean one to re-apply.