Put chopped kale pieces (they will shrink, so 2-3 inch pieces is great) in to a bowl or ziplock bag and toss with oil. Range of how much oil to use is dependent on the size of your kale bunch. Make sure you use enough to coat all kale pieces, without drowning them. I usually find 2 tablespoons oil is sufficient for a ziplock bag of kale that is 2/3 full of kale pieces.