Take for instance a typical day in the life of an individual. When the person wakes up in the morning the world comes into existence as far as he/she is concerned. If he feels bliss within himself after a nice deep sleep, he tends to feel happiness in the world around him. He is unaffected by problems around him, but tries to solve them if possible. His entire day feels positive and productive.
On the other hand if the same person wakes up after a poor sleep, he lacks bliss in his heart and his "mood' is not so good. He tends to get affected by problems around him. He may even compound the existing problems rather than helping to solve them. He may wish that the day ends soon.
What matters here is how the person feels at the moment of his awakening. The state of his conscious mind when he starts perceiving the world, determines the quality of the rest of the day for him. That "consciousness', whether it is blissful or lacks bliss, is the basis upon which his day is built. All other things are secondary.
Once this foundation - the principle of consciousness - is understood then we have a way to influence the state of our own consciousness and the quality of our day. All we have to do is to ensure that we have a nice sound sleep by avoiding things that can disturb our feeling of happiness during the previous day.
Once we have a good sleep the next day dawns well and it is easier to maintain the feeling of happiness on subsequent days, provided we do not fall prey to negative emotions that can disturb us. One way of perpetuating happiness is to keep contemplating on the bliss that persists for sometime after a good night's sleep during the course of the day.
When we understand that everything in a day's life is a play of consciousness then we can ourselves play with our consciousness. Control of consciousness leads to better control of mind. Better control of the mind means better control of what is done with the body and better health of the individual.