We want as much as possible, our day to be as meaningful as it is may be. As useful as it may be, thus productive. If you are working from a 9-5 job, you want as much as possible get everything you can to squeeze in every detail to finish the job required. If you are working on your business, you want everything to be finished, for example get the most sales quota for the day.
One super useful tool is to write it down, journal everything, so it is easy to cross out the things required during the day, you will be surprised how your day will look like.