Happiness is an inside job!
In order to be efficient and motivated to get a hard (or simple) task done it is essential to estimate a realistic timeframe for accomplishing the task. Focus-time is something that doesn't last for ever and your capability to focus is limited. Setting a realistic timeframe and clear end goal will help to be motivated. Combined being focused on one focus and starting with the hardest thing first will enable you to produce the most over the day.
Jorian Bos - PhiloSelfie Founder