Hi Shabab, there are some great answers written so far.
I really like how David mentioned planning his days ahead. There's a powerful system I use that is a twist on that, for getting work done day-to-day. It's called the Pomodoro Technique.
What makes the Pomodoro technique beautiful from an organizational standpoint is having the 'Activity Inventory' and the 'To Do Today'. You can chalk your 'Activity Inventory' full of worthwhile tasks that will eventually get transferred into the 'To Do Today' and completed.
From a productivity standpoint, the technique works well because it leverages focused and intense work (sprinting), followed by resting. This is how high-performers naturally operate.
At the beginning of each day of work, you take 20-25min to organize what you will work on by listing what you want to tackle in the 'To Do Today'. For me, this organizing session is like my Zen part of the day where I'm drinking English breakfast tea and getting ready for battle.
If you're really smart about it, you 'eat the frog first'. What this means is to pick the task that is the scariest, requires the most creativity and probably is the most important thing that you could do in the day. By prioritizing and scheduling it first thing, all the following tasks in the day are relatively easy and subsequently get taken care of.
Here's a few resources for the technique:
2 min intro video - http://www.pomodorotechnique.com/get-started/
The free PDF book (more in-depth) - http://www.pomodorotechnique.com/book/
A good 25min timer - http://www.focusboosterapp.com/
Hope you find something helpful here! Cheers, Trevor
p.s. on a more macro-level, you can't go wrong with a NeuYear wall calendar - http://www.neuyear.net/products/2013-calendar-uncoated