Determine your peak productivity time based on your energy cycle and habits. Schedule the things that need to get done during your peak energy cycle and then add everything else. I am a morning person, so I do as much as I can on my computer and in my studio before 3:00 pm and pack up orders, take photo's, and respond to e-mails after that. I know my Mom is a night person and does most of her work after 10 pm.
What time of the day do you have the most energy?
Know in advance what you want to accomplish. Break down what needs to get done into manageable steps so at the end of your work session you can see results. I usually write a list before I go to bed, so I know what I want to get done the next day. It helps keep me on track, so my day does not get away from me, which is easy when you work on the computer which has lots of distractions.
Does a to-do list help you?
Prepare your workspace for the next day. When you are done for the day it may be easy to just leave things all over, but you will accomplish more if you start your day with a prepared work area. This is the hardest for me, because I like to create in a little bit of chaos, but I do put away papers and pull out projects in my office area, so I am ready to go the next day.
How do you prepare your workspace?
These are some simple ideas to help organize your day. There are many resources online about time management try google.com and hundreds of book on the subject, check out amazon.com for more information.
I hope you find the time you need to be most productive during the day.