At its heart is the principle of dividing time into pockets of focused action. 25 minutes followed by 5 minutes break is the recommended standard approach. Long enough to get stuff done; short enough to keep focus intense. It starts to change your concept of time. From an abstract stream of uncontrollable resource to a sequence of 25 minute "Pomodoros" each one a finite pocket of opportunity to complete a section of your task. Pomodoros become sacred opportunities for action. This energises you to the task in hand. It encourages you to "protect" the Pomodoro from distracting interruptions. There's even an excitement from the internal game of making eachPomodoro more effective than the last. It is the single most effective technique for getting stuff done I've ever used; at least doubling my productivity.
Once the basic technique is mastered you'll move on to advanced techniques of estimation. Soon you'll be accurately estimating the time required for tasks and your capacity for achieving objectives in a day. Invaluable for helping you focus on the stuff that really matters.
I implore you, throw out the tedious techniques on Outlook task management. Do away with hours of unproductive slog. Tune into the tick tick tick of the tomato and rediscover just how much you can achieve in a few hours of focused attention. Pomodoro, thy name is action.