A big time-waster is continuing to work on something when it’s done. After a while, you’re not making it better, you’re just making it different.
And if you carry on, you’ll start making it worse.
Yes, you may be saying, but how do I know when it’s done?
This is one of those times that it pays to listen to your gut. Often we know it’s done but we keep going because the next step after ‘done’ often is submitting it to outside scrutiny and that’s scary.
If you’re still messing around, stop, take a deep breath, and turn your attention inside. What are you feeling?
If it’s fear, then stop.
If it’s just insecurity about the ending, be honest about whether the last few rewrites have made it better or just different. If just different, stop.
Another tactic is to leave it alone for a little while. Turn your attention to something else for a couple of weeks. Then go back and reread what you wrote. Does it satisfy? Does it feel complete?
If so, probably it is.
(For powerful strategies for using your time more effectively, get my book, "Focus: use the power of targeted thinking to get more done." It's published by Pearson and you can get it now from Amazon and other online and offline book sellers.)