Academia has not kept up. By some estimates, people waste about 2 hours per day. Being successful doesn't make you manage your time well. Managing your time well makes you successful. Doing things right is not as important as doing the right things.
Planning is Important Failing to plan is planning to fail.
Have something in view that you're waiting to get to next. You don't find time for important things, you make it. Defend it ruthlessly, spend it alone, maybe at home. Find your dead time. Schedule meetings, phone calls, and mundane stuff during it.