There are many good leafy ways but you could also mist with olive oil, salt it and cook in a low oven [275?] for 10-12 minutes and it should turn into flavorful chips. May want to oil the cookie sheet though.
One thing we do often is cut the leaves off from the main stem, chop the stem up into like one-inch pieces, roughly chop the leaves, and then do a little stirfry where the stems get a couple minutes lead time to soften up before the leaves go in.