Each evening, I fill out a schedule for the following day; first listing all of the things I have to get done, and then relisting them in numerical order of importance.
At days end, I circle the unfinished tasks, and make out a new schedule for the following day, including the unfinished business.
So long as I am able to complete most of the tasks on my daily list, I feel that I am making a good bit of accomplishment and progress.
The unfinished tasks I chalk up to having an unrealistic outlook on what I am actually capable of doing!