The same way I make most my dark leafy green vegetables. Light oil in my wok, throw in some garlic, cook a bit, throw in the chopped stems first, then leaves. Make sure the veggies are still a little wet from washing. A little salt.
We treat dark leafies the same way as Jennlin, except we dice up a bunch of onions and get them good and translucent, then add in garlic and greens. Also like to use flavored olive oil and add a dash of vinegar. Make sure the greens are a little damp from washing. We often add maybe a tbl of water, then cover for about 8 minutes, stirring once, then uncover and season with salt & pepper.