Each pattern has various stages that it goes through as the horses show more and more white, so horses of a particular pattern will have progressively more white in fairly predictable manner. Soooooo - with this all in mind, let me try to explain each pattern. Often the markings are blotchy or roany. In the most extreme cases, dark hairs will remain along the topline, ears and tail. Tell tell signs - white extending under the jaw.
Eyes usually remain dark.
It looks like you dipped the horse, feet-first, into a vat of white paint, and it spreads just like the horse was getting dipped deeper and deeper into the paint. In the most extreme individuals, the ears and topline will remain dark. The edge of the markings is crisp like a tobiano. Horses that consistently pass on blue eyes almost always carry this gene, and splash overos always have two blue eyes. LOTS of face white - even in minimally marked horses the entire head is often white.