Use batching and a feedback system to be more productive

Use batching in the short term.
Schedule your high-intensity tasks into a single, long stretch of time so that you can quickly master them. Focus on one thing at a time, as splitting your attention between multiple things reduces your productivity and quality of work.

Use batching in the long term.
Take stock of your work activities in the coming months. Then work on a single activity for a week or more, leaving other tasks for later. Continuous practice is the best way to perfect your skills.

Create your feedback system and measure your progress.
Create your own feedback system by tracking the output of your work. Use a concrete number of productive hours, sales, money, etc., and identify how these factors affect the quality and efficiency of your work.