During the month of May and the first half of June, I kept a time diary. Several times throughout the day (as often as possible, in fact), I recorded how I had spent my time in as much detail as possible, without judgment, and saved all of these notes.

After allowing a couple months to pass, I sat down with all of these notes in August to try to piece together how exactly I spend my time, how I was wasting it, and how I could use it better.

I found this to be a really useful experience, so I decided to share it with you.

What’s a time diary?

Simply put, it’s a document where you record what you’re doing throughout the day in as much detail as is reasonably possible. So, for example, I might write:

6:45 AM – Woken up by my daughter and struggle out of bed

6:50 AM – Make breakfast for the family

7:10 AM – Eat breakfast

7:25 AM – Get together clothes for everyone

7:30 AM – Everyone gets dressed

7:45 AM – Take children to preschool

8:10 AM – Check email

…

You get the idea. The more detail you can add, the more useful this will all be.

What’s the use of a time diary?

When you are just entering the data into the diary, it doesn’t really serve any use at all. It’s just a recording mechanism.

Instead, a time diary comes in handy later on, when you have a month or two of data to look at and analyze. With this level of information, you can pore over the data carefully and often find some very interesting things about how you use your time and what you could do to use it more effectively.

Five useful things I got out of my time diary

The easiest way to demonstrate how a time diary is useful is to jump straight to the conclusions. Here are five things (out of a much larger set) that I’ve concluded from my time diary.

I would initially get a “hunch” about these things while reading the entries, then I’d find some way to extract that information to see if the “hunch” was right. Often, it was.

I used the May and June 2011 pages on a wall calendar with large spaces for the checkmarks and numbers I mention below. This let me easily compare days.

1. A poor night of sleep doesn’t affect me until two days later. Let’s say that I don’t get much sleep between Tuesday evening and Wednesday morning. I’ll usually be just fine on Wednesday, but I find that on Thursday I’ll waste a bunch of time and be much less productive than usual. I suspect that on Wednesday, I’m running on some sort of reserve, and my sleep on Wednesday recharges that reserve but doesn’t recharge me all that much.

I found this fact by taking the calendar, checking each night that I got less than seven hours of sleep with a red marker, and writing the number of obviously unproductive hours on each day with a black marker. The source of the information, of course, was my time diary.

I can change my behavior because of this by accounting for lethargy on those days. If I get a poor night of sleep, I’ll try to be extra productive on that following day because I know that the day after that will be a poor one. I’ll save mindless tasks for those days.

2. The more I interact with my children, the bigger the productivity boost is the following day. If I have a day where I spend a ton of time just with my children, the next day is usually a productive one. I’m not sure why, actually. However, I’ll say that yesterday, we took the children to the grocery store, watched a movie with them, rode our bicycles to a park, played there for a while, and rode home, and today I feel really productive.

I found this fact by counting the number of hours spent each day with my children, then comparing that to unproductive hours the following day.

I can change my behavior because of this by keeping my commitment to spend focused time with my children each day. Not only is this interaction good for both of us in that moment, it apparently also bumps up my productivity down the road. In fact, it pushes me even more toward scheduling “special days” where we do things like go to the Science Center of Iowa together.

3. Time spent reading usually increases my productivity for the next two or three days. One thing I measured is how many articles I completed per day. I found that if I spent two hours or more on a given day reading, the following day would see production of about one more article than average and the day after that would see a bump of about half an article more than average. I think the connection is that reading helps me with my ability to come up with phrases for the ideas floating around in my head.

I found this fact by simply noting the time spent each day reading and the number of articles produced each day. I averaged the number of articles I am able to write in a “working day” and then would compare that to the number of articles on each day, writing a + or – figure in the square as well.

I can change my behavior because of this by minimizing the little amount of television I currently watch and replacing it with a good book.

4. The longer the gaps between time spent cleaning my office, the lower my productivity. If I stop and clean my office once every week or two, I tend to be more productive than if I just let it go for a while.

I found this fact by using the calendar, recording the number of unproductive hours each day, and marking the days I cleaned my office with a pink highlighter. I found that the farther from an office cleaning I was, the less productive I was each day. It was a small impact, but a real one.

I can change my behavior because of this by cleaning my office more regularly. I’ve started setting aside time on Friday afternoons solely for the purpose of cleaning things up and making little changes, like installing a wall-mounted bookshelf for some of my most frequently accessed books.

5. My optimum amount of sleep is about eight hours, and it’s best if I wake up on my own and am not awakened by someone or something else. If I sleep much less than that, it tends to move into the “poor night of sleep” category and affects me down the road. If I’m awakened by an alarm clock (on occasion) or a child (much more frequently), it definitely has an impact on my day.

I found this fact by again using the calendar, checking the nights where my sleep was interrupted with a green marker, and writing my unproductive time on each date with a black marker. It works well with the first fact I discovered.

I can change my behavior because of this by going to sleep a little earlier. If I go to sleep earlier, I tend to rise with my children or even before them and I rarely need an alarm clock. This creates more naturally productive days.

Simply put, the entire purpose of a time diary is to figure out simple things you can change that make a big impact on your day-to-day life. I learned how much of an impact spending a couple hours cleaning my office can really have. I learned how direct the positive impact of reading is on my life. I learned that going to bed around ten during the school week is probably optimal.

These little things make a huge difference in my weekly productivity. They seem like small tweaks, but the impact of these tweaks is felt during every hour of every day in the form of increased energy and alertness and mental productivity. This adds up to more income and more life enjoyment as well.

Those types of discoveries are well worth the time that such a task takes up. It really can change your life in a positive way.