Exercise/walking is good, preferably in sunlight. A light box. A 3-foot fluorescent shop light does the trick. Light can be placed to the side. Pray for spring.

Oh yeah, definitely the exercise! It's so easy to say to myself "well it's way too cold to go for a walk today" but that doesn't mean laying on the couch is my only alternative.
Also being around people. The change of scenery. I recently watched a football game with guys who were speaking almost exclusively Spanish --which I don't know! And I hate football! But it was a fun nite outside of the house!

@zonker yes I should of went for a walk today. I said that to myself today too cold to walk. I should of went anyways but dang it was cold today.

Make sure you're eating a very healthy, preferably organic as much as possible, diet...

Lots of fresh veggies and fruits, especially the berries.

Organic, raw milk or soy milk, almond, rice,coconut milk.

Green smoothies are so good for us! i make mine with unsweetened soy milk, some organic spinach and kale, berries, flax seed(1 T) and either stevia or agave syrup for sweetness...it really gives me energy.

Have you ever tried chia seed? They are teeny little black seeds and are so healthy...1 T is a serving for most people...they have a nice nuttty flavor..i just pop em in my mouth..so crunchy and good. Look for them in a health food store, preferably organic.

Right, greens are great for fighting depression. The more raw the better. I sometimes just eat raw broccoli or purple cabbage and salad dressing while watching tv.