Source: Widely used scheduling practice; strongly advocated by Cal Newport
Assign every part of your working day to a specific task or type of work in your calendar. You plan the day in advance rather than reacting to whatever arrives.
When to use it
Use it when your days get swallowed by meetings, messages and interruptions.
How to apply it
Review your tasks and priorities for the day ahead.
Divide your calendar into blocks and assign a task or task type to each.
Group small similar tasks, such as email, into a single block.
Leave buffer blocks for overruns and unexpected requests.
When plans change, re-block the rest of the day rather than abandoning the plan.
Tip: Expect to revise the schedule; the value comes from deciding deliberately, not from sticking rigidly.