Freelancers must learn to be as productive as possible. You have to juggle multiple responsibilities within your business, work with various clients, etc. If you aren't productive, you can easily fall behind and have upset clients within one week or less.
However, there is one surefire way to increase your productivity: get ready for work.
You will be surprised at how much you can get done when you have shifted your brain into working mode. The quickest way to go from 0 to 60 (productivity style) is to get dressed for work - all the way down to putting on shoes. I explain more details in this video:
It works, believe me. If you don't believe me, try it, and if it doesn't work, you have full permission to give me a good cyberslap :-).