Select an exercise to do today which you know will require a special effort of will. The chief aim of this exercise is to stimulate your ability of effort, and to help you develop the habit of readiness of willing.
You will walk to work or get off the bus several stops early etc. Or go for a walk in the cold weather. You believe the exercise will benefit your health.
Or you will avoid such foods that are classed ‘junk foods’ or that you have a particular weakness for.
Or you will definitely do some exercise that your do not enjoy or is particularly hard – though you recognise the benefits this exercise has to your best development.