All this depends on your couch fabric type. Is it leather, faux leather, suade, microfiber, or tapestry fabric?
You can get the manufacturer's info (there is usually a label or stamp on the bottom of the unit) , or call where you purchased it to get the manufacturers info.and call them. They will be able to tell you how to clean it.
I have heard that WINDEX and rubbing works. If the pen is water soluble, use soap and water. Or with Colgate white paste toothpaste rub in with a toothbrush with a little bit of water (works great for pen, pencil and markers on walls, too). Blot, and then repeat until it comes out. If that does not work, I have used Enzyme fabric cleaner and soap. A long time ago I used foam carpet cleaner on one, but first try the windex.
As for throw up and mattresses. Go to the pet store and get "Nature's Miracle" spray. It is an enzymatic cleaner that won't hurt any thing, and it gets rid of the the smell and the stain comes out. Later clean with foam carpet cleaner.
Good luck.
A little about me: I'm a SAHM of 9 who now range in age from 32 down to 9. I had a day care center as well, and these ideas have been put to the test.