Usually I wake up with negative thoughts but as the day progresses I have good experiences with others, and I enjoy walking, reading, writing and eating, so by about five o'clock I have left all my negative thoughts behind.
Sometimes I think I would like to have positive thoughts all the time because positive thoughts bring positive emotions, but my negative thoughts are persistent.
So rather than trying to banish my negative thoughts I have started to listen to them to see what they are saying, and whether they are important, and how I should integrate them into my life.
So I find my negative thoughts are protecting me. So if I listen to them, and take notice of them, but continue with what I want to do, it seems to work.
For instance, I wanted to meditate at night surrounded by candles standing in a creek running through an urban park near me. Immediately I had negative thoughts that people would think I was weird in the creek at night surrounded by lit candles. This negative thought is probably true but then I thought there is no reason I can't meditate in the creek without the candles. And so I listened to my thoughts warning me of possible danger, but then went ahead, taking this advice.