I'm from the south and have experience with collards. First: cut out the heavier stems. 2. washing. I put mine in my washing machine on delicate, warm and run a cycle with an extra rinse. Saves a lot of time hand washing. Don't do this with other greens or you will have confetti.
3. Cook with ham hocks (if you like) or fresh pork (I prefer boneless porkchops) and salt til done.