The Essential Executive, tl;dr-ified
Chapter 2: you need to protect your time for best effect.
Step 1. Track it. I started a log last week using an iPhone app. A notebook might work too. What are you spending time on? Nobody can reliably guess.
Step 2. Manage it. Cut it back. Skip things, delegate attendance, don’t invite everyone, don’t make a call or meeting for a five minute task, or just say no.
Now you are in a position to get somewhere. The key move is next:
Step 3. Create big blocks of time like 3-4 hours. Meet people for 90 min not 30. The really big important stuff (not doing email, not catching up on some little tasks), the big decisions or work you need to do: takes deep time commitments.
Drucker is huge on “do the main thing” (biggest impact, only the #1 thing) and he is emphatic that this thing take time. Attention, concentration, no interruption, no rush, plenty of time for second thoughts.