I harvest every year on Whidbey. My method is still hunting as there are plenty of deer moving around. Most have been harvested right after legal light as they really tend to move to their feeding spots at that time. Try to get in a hour before light and set up a ground blind or have a stand up. Sit still and you will hear them moving through the brush. I wait until their head is obscured by a bush or tree before lifting my bow so they don't see the movement. Good luck on filling your tags and post some pictures of your hunt!
