If you're feeling like your life is going completely amazing, then warn someone. I'm not saying this will happen, but it does with me. When I'm feeling like my life is going amazing, a couple of days later I will feel like my life is CRAP. So I make sure to warn one of my friends. (The first thing on my list of making me feel better.) That way when I feel like being depressed, she notices and tries her best to make me feel better.
Now I was lucky, because my best friend now also has depression. Hasn't been diagnosed, but the feelings resemble depression.
So there are probably some people out there that are thinking, "I feel like I don't have anyfriends so what do I do?" If you're in that situation then maybe the first thing is music. So in that situation make a playlist of all of your favorite upbeat songs. If it's books then set aside a book that is cheerful that you read only when you don't feel good. Something along the lines of that would be perfect for feeling good.
Now I must say that this will probably not work every time, but KEEP. WITH. IT! That's the only way to feeling better.
