But as we all know, "surprises" are an inevitable part of life. Things USUALLY don't go our way. So over the years, I've developed an approach to flexibility that allows me to handle those surprises. It includes:
1) Learn to roll (and block) the punches.
Sometimes, we have to be ready to have our ideas and plans kicked to the curb. Honestly, this first step is all about approaching the day with the right attitude. Realize that STUFF happens and it's okay if we get knocked off course. Dust off your knees, try to identify the top (I usually aim for 1 or 2) things that have to be done that day and focus only completing those tasks. Or perhaps, ditch the schedule altogether if an emergency calls for your full attention. The only concern is if these so-called 'punches' are landing more often than not - that's when the next steps can be extremely helpful.
2) Be realistic in making your schedule.
Do not follow the methods of airlines - overbooking is not necessarily conducive to productivity. I, too, want to maximize my day and get the most out of it. However, overextending one's time can lead to missing more important things, like a friend's birthday party, your niece's soccer game, or that meeting with a potential client. The litmus test: if you secretly say to yourself "there's no way I'm going to get all of this done today" before you finish writing your list, chances are you're overbooked. And if you're overbooked, surprises can send you into a level of stress and anxiety that are not healthy from any viewpoint.
3) Add buffers to your schedule.
Consider travel time and incorporate it into your time frames so that you are not promised to be somewhere before you even have a chance to get there. Add a few minutes in your scheduled times to work on projects for unintended interruptions, like phone calls from your Mom or a surprise visit from your boss. Unless its in the same building or area, try not to schedule back-to-back appointments. So if something "unexpected" does happen, you have a bit of a cushion to rearrange and reschedule things if needed.
I hope this helps, as it has helped me gain a better understanding of my own capabilities without pulling my hair out to get there. Here's to living in an optimal condition!!!