The tarp's ridge-line (the rope that goes down the middle of it) can be hung with the tarp inside it's stuff-sack. This keeps it out of the way until it is needed.

Next, it can be hung "wide", where there is more protection from wind & storms. This is how I almost always have it, because of the nature of storms where I live.

Finally, it can be hung "long", where two corners of the rectangle are the ends. This is nice if there is light rain, and when hung flat like this it creates a kind of porch you can cook food under. I rarely do this though, so I don't actually have any pictures of it in this configuration.