I put a lot of emphasis on entering information into my planner. The hows, whats, whys, whens, and wheres matter!
But I also have a simple system for use of my planner, so that I can track what still needs to be accomplished. The "in progress" marks matter a ton, as they keep me on task and they let me glance quickly at the information in my planner and make fast decisions.
Here's what the system looks like in progress:
The In Progress System
*@ = waiting on something or someone before I can do the task (pending)
*O = task ready to be done
*-O = task is started, but not complete (this is particularly useful if I can't continue yet, like laundry in the wash, but not dried and ready to be put away)
*O (checked off) = done
*O (arrow) = moved to another day
*O (X'ed through) = deleted
TIP: Regardless of code, highlight any task that is checked as done, moved, or deleted, so the rest of the tasks jump out to your eyes.