Slow down and remember this: Most things make no difference. Being busy is a form of laziness—lazy thinking and indiscriminate action.
Being overwhelmed is often as unproductive as doing nothing, and is far more unpleasant. Being selective—doing less—is the path of the productive. Focus on the important few and ignore the rest.
Parkinson’s Law dictates that a task will swell in (perceived) importance and complexity in relation to the time allotted for its completion. It is the magic of the imminent deadline.
The best solution is to use both together: Identify the few critical tasks that contribute most to income and schedule them with very short and clear deadlines.