Wrap in damp paper towel or plastic bag and refrigerate for up to 1 week.
Chips: Drizzle olive oil onto kale. Using hands, rub the oil into the leaves so the pieces are evenly coated. Sprinkle with salt and pepper, or any other spices you might want (Google search for a ton of ideas). Place on a baking sheet, spreading evenly in a single layer. Roast until crispy (8-10 minutes) at 400 degrees. They can burn easily!
If you don't like them as a snack, try crumbling them up and storing in an airtight container for a long time (see below). I do this, and then add it to soups/stews/sauces throughout the year as a "spice". It's a good way to sneak some veggies into my husband.
Freeze: wash, de-stem, and blanch leaves for 2 minutes (dunk in boiling water for 2 minutes), rinse in cold water (ice bath) to stop cooling. Drain and freeze. I like to lay fruit and veggies out on cookie trays to freeze, then pack them into plastic bags after they are frozen.
Dehydrate: Assuming you don't have a dehydrator (if you do, follow those directions!), wash, trim off stems if desired, and pat dry. Place a single layer on a cookie sheet, pop them into your 200 degree oven for ~ 20 minutes. Keep your eye on them towards the end -- they can burn easily. They may need a little more time, so pay close attention. Once you have the timing figured out for your oven, write it down somewhere so it will be easier next time.
Crumble up those greens, and then add them to eggs, smoothies, soup, stews, sauces--whatever you can think of! Re-use one of those Parmesan cheese containers (not that you buy that pre-packaged convenience stuff!) to make it easy to sprinkle it into everything.