Okay, I don't have a camera, so I can't show you. However, I will do my best to explain.
In my attempts to find a style of covering that doesn't look specifically Muslim, I found a pretty casual way of wearing the shayla scarves. For this, it is better if you have longer hair that you can put in a bun.
First, you center it on your head with the ends hanging in front of you (like you would if you were going to pin it at your chin -- but you don't pin it!).
Then you pull the ends tightly from the front, so that they hang down your back like a ponytail. Don't let them go, or you'll have to start over!
Then you twist the ends at the nape of your neck so that they hold the scarf in place, and pull the ends in front of you so that they hang like pigtails. I leave them hanging down, since the weight helps keep the scarf in place longer. They can get in the way, so I don't recommend using a very long scarf.
The end that starts on your right will be on the left, and the one that starts on the left will be on the right. It's very simple, and the small excess of fabric that is left in the back covers your bun. Do a double check in the mirror to make sure it's covered, though -- it can be sneaky and just sit on top of your bun.
The only downside is that I have to redo it several times a day, as it slips up and starts showing my hair. : P I haven't tried wearing an underscarf, though, so I'll give that a shot and see if that helps. : )
Still, it is very comfy.