Writing 3 pages every morning upon awakening, whatever comes into your head and before you go about your day. You can shred them afterwards. The discipline of writing helps rewire the brain. Julia Cameron explains the process in her book The Artist's Way. I read that years before I heard of a similar technique in Cathy O'Brien's work. It has saved me many a time. Nobody reads it. Anything at all that comes in your mind, just write it out (not typing or using a keyboard). It is the one thing you can always do. If you were in recovery for alcohol or drugs, they would also recommend you start your day with a daily reflection or prayer and meditation. Those have worked for many people I know, but I always do the morning pages first.