Here is one thing I know of after 26 years: everyone has the same amount of time in each day. Sounds obvious enough, right? The thing that has been bothering me about myself lately is that I'm wasting time. Now, I am a firm believer in "wasting time" to a certain degree. I think you need designate times, particularly on weekends for example, to do nothing. It's called resting, or taking a Sabbath (though Sabbath includes more than just doing nothing). So that's not the kind of wasting time I'm talking about. What I'm being bothered by in my own life is the times I'm choosing trivial, meaningless things above things that could make me more effective for the Lord.
This is a season in my life that many people don't get. I've moved away from many family and friends with my wife for a time of studying, preparing for whatever God would have me to do with the rest of my life. And I'm making pretty good use of the time when it comes to studying and trying to soak up what I'm learning. But I want to do better. The most effective people, in any arena, all have the same 24 hour periods of time that any of us do. What's the difference? They make the best use of their time. To be sure, some people who are "effective" are neglecting some areas of their life - kids, wife, husband, health - in order to succeed in business and/or church. But a great number of very effective people aren't letting other areas slide in the name of being successful. They are just disciplined, making the best use of their time. And, from a Christian standpoint, they know they are doing exactly what God calls them to do.
Ephesians 5:15-17: Look carefully then how you walk, not as unwise but as wise, making the best use of the time, because the days are evil. Therefore do not be foolish, but understand what the will of the Lord is.
A more literal translation of "making the best use of the time" is "redeeming the time", and I like the emphasis on redeeming. As Christians, we are to use the time God has given us on the earth for his glory, going about the kinds of things he's made us for - accomplishing his will. That will is both general and specific. There are many things all of us are to involved in - helping others, loving people in the name of Jesus, gathering as Christians regularly to worship God, confessing and repenting, and much more. And then there's specific things God has wired us for. And while the easy way out is "It's too confusing for me to know what God has made me for," I believe we need to push beyond that and ask God what he's made us to do. What are you passionate about? What are you good at? What do people encourage you to do? God has wired us in our personality, in are genetic make up, and with spiritual gifts for believers in unique ways to be used for the encouragement of others and for God's Kingdom.
So, I'm going to redeem the time. I still need to put my finger on specifics, but I will. Maybe I need to sacrifice habits that are counter-productive. Maybe I need to pick up more books. Maybe there's things I'm not even aware of. But one thing I do know: God has given me an allotted time on earth before I'm in his presence forever, and I will use this time for his glory.