Which is the most important tool to help you get the most done? A calendar or a to-do list? Skip the to-do list and use your calendar. Break the calendar down to the smallest section of time.
Even minutes can be scheduled. 15 minute segments or 30 minutes. Time is precious and using a calendar will help you maximize your time results.
If you can't find a place on the calendar to work on something it will never get done by putting it on a list.