One of the best (if not the best) resource on time management I've ever found was a lecture by Randy Pausch.
You can find his lecture here: https://youtu.be/oTugjssqOT0
Who is Randy Pausch?
He was an American professor of computer science, human–computer interaction, and design at Carnegie Mellon University (CMU) in Pittsburgh, Pennsylvania.
Pausch learned that he had pancreatic cancer in September 2006, and in August 2007 he was given a terminal diagnosis: "3 to 6 months of good health left". He gave an upbeat lecture titled "The Last Lecture: Really Achieving Your Childhood Dreams" on September 18, 2007, at Carnegie Mellon, which became a popular YouTube video and led to other media appearances. He then co-authored a book called The Last Lecture on the same theme, which became a New York Times best-seller.
Pausch died of complications from pancreatic cancer on July 25, 2008.
His lecture is inspiring and who could better explain how to manage your time than a person who only has a few more months to live. I has the outmost respect for Randy Pausch and his final lecture has made him immortal.