80/20 rule

Credit to Perry Marshall for a short article to get started on this.
https://www.entrepreneur.com/article/229294

What are top 20% producing 80% of results or revenue?

What are top 20 percent causing 80% of annoyance, wasted time etc?

Work it both ways. 

Focus, systems, work smart by not working every minute, and reflect

1. Work on a project for 30 minutes at a time. 
2. Build a system for the big projects so I don't have to remember it all
3. don't work the last 30 minutes: instead end well and prep to make it easy to pickup the next day
4. Reflect and learn

From the bbc article for some tips

Try to wrap up for the day at a point that will be easy to pick up the next day.

Self-reflect. At the end of each month, take a cold, hard look at your calendar and how you spent your time over the previous four weeks. Are you proud of how you used your time? Did you get a solid return on investment from what you chose to do? Are you following the suggestions in this column to stop wasting time? Even the best intentions aren’t enough to break old habits. If you’re serious about this, monitor how well you’ve been doing. It’s one of the best ways to get anything done. Don’t just say you’re going to stop wasting time, or assume that you are, but check and make sure. Ready? Schedule your check-in right now, one month from today.

Thanks to  Sydney Finkelstein

21 April 2016http://www.bbc.com/capital/story/20160419-what-does-it-really-take-to-stop-wasting-time