Define the problem clearly
The definition of the problem will be the focal point of all your problem-solving efforts. Start by very clearly defining the problem in its entirety.
There will be times during the day when you have high energy levels and you can get a lot of work done very quickly, and other times when your energy levels drop.
Rather than work harder, you can work smarter. When you work smarter, you remember what you are trying to achieve and you focus on tasks which help you to achieve this.
A job half done needs doing twice. Finish what you can in one go.