Another distraction is when people turn up at your desk while you're in the middle of something. The best thing (for you) is to politely ask them to come back after 30 minutes (or whatever time you will take to complete what you have already started). Otherwise, you start one thing, someone asks you to do something else, the phone rings after sometime....and in the end, you haven't even completed ONE task properly.
Be polite, but FIRM. YOUR work first. OTHERS can wait!
May not work for everyone, but works damn well for me! :)
