You come to office and the first thing you see is a dirty workstation. How do you feel? Disgusted, right. A tidy desk invites you to work on it. All you need to do is to clean up your desk before you leave for the day.
Organize your files
Keep your files--electronic as well as paper--in an organized manner. Neatly labeled paper files will help you track your documents saving both your time and effort.
Similarly, electronic files with indicative names like iom_5jun_operations.doc in IOM directory will tell you that this is the IOM on June 5 regarding operations. You won't have to do a file search and click at twenty files (with similar names) to find out the one you are looking for.
Apart from this, keeping stuff organized satisfies your aesthetic needs and will make you feel better.
Plan your day
Plan your day as to what you want to do. Make a to-do list and prioritize your activities. Assign approximate time to your planned activities. Don't forget keeping some time for unexpected assignments. This would help you remember things you want to accomplish.
Take a break
Have you ever tried finding out how is the weather outside? Sounds stupid. But this really works. Take a break. Don't work for more than two hours at the stretch. After two hours of continuous work take a five-minute break.
Talk to friends, take a stroll, play a game, or do anything that delights you, and you would come back to work with double energy.
A better tomorrow
List down the things you want to do the next day. Paste the list on your desk at some visible place or send yourself a mail-whichever way you feel better. When you come to office the next day, you'll have half the day planned in advance.