Time Management is critical if you want to succeed as a freelancer or a manager in any business. Here are books for recommended reading...
Getting Things Done: The Art of Stress-free Productivity (by David Allen).
Time Management from the Inside Out, Second Edition: The Foolproof System
for Taking Control of Your Schedule -- and Your Life (by Julie Morgenstern).
No B.S. Time Management for Entrepreneurs: The Ultimate No Holds Barred Kick
Butt Take No Prisoners Guide to Time Productivity and Sanity (by Dan Kennedy).
All available at Amazon.