Every night for the next week, set aside ten minutes before you go to sleep. Write down three things that went well today and why they went well...Writing about why the positive events in your life happened may seem awkward at first, but please stick with it for one week. It will get easier. The odds are that you will be less depressed, happier, and addicted to this exercise six months from now.
I would not advise people to buy a car or house without making a list. You will probably improve your intuitions by making a list and then sleeping on it.
Ten minutes of a smartphone in front of your nose is about the equivalent of an hour long walk in bright daylight. Imagine going for an hour long walk in bright daylight and then thinking, "Now I'll get some sleep." It ain't going to happen.