Over the 20 years I have spent coaching executives, there is one topic that comes up at almost every level of leadership: delegation. Most leaders know that they should be delegating, and many of them know how to do so. The stumbling block that holds most leaders back is knowing what to delegate.

When I ask executives, “What, according to you, should you delegate?” I can see them scanning their memories for tasks they would be comfortable handing over to someone else. Rarely have I seen them come up with anything significant. As a result, they talk about giving up a few low-risk activities but miss the opportunity to hand over anything substantive and meaningful. The truth is: Many senior leaders carry out tasks that might appear seemingly small but are surprisingly time consuming, and the value they generate isn’t proportional to the time spent on them. In essence, these tasks rob senior leaders of valuable time that can be spent on more strategic, higher ROI activities.

To help my clients give visibility into (and measure) these tasks, I ask them to use a classic time management tool for identifying inefficiency and redundancy: a time log. Instead of relying on a leader’s memory, a time log presents data of where their time is actually being spent.

Consider the example of a CFO (let’s call him Mike) I was recently coaching. Mike had been promoted from a corporate controller position internally. He knew at a conceptual level that he should be reallocating how he spent his time but was struggling to identify what he could delegate to his team. Once he had two weeks of time log data, he quickly recognized all of the tasks he carried forward from his old job into his new one. There were some reports that he was still running for the CEO, as well as some reconciliation tasks that he had not gotten around to teaching his new controller how to perform. He also spotted several meetings he was attending that would be better attended by a member of his team. In all, Mike found about 20 hours a month of activities (tasks and meetings) that he could delegate. He learned so much from keeping his own time log that he asked each of his direct reports to do the same.

While a time log might feel tedious, it can be a very effective way to start freeing up your day for more strategic work. If you’re ready to put this into action, I recommend approaching this exercise in four steps: capture, analyze, delegate, reflect.

Capture

Start by creating a spreadsheet and dividing the workday into 15-minute increments. Some people fine tune this with 10-minute blocks, others broaden it to 30 minutes. Those are okay, too, but I do not suggest going all the way up to 60 minutes, as a lot of the smaller tasks will start to get lost.

While there are excellent apps out there for time tracking, many of them have a decent-sized learning curve that results in leaders giving up before they get going. If you have an app that you like and will reliably use, you should do that. Otherwise, the humble spreadsheet is an easy tool most of us know how to use.

Once you have created your log, take some time, two to three times a day, to reconstruct how you spent your time over the prior two to four hours (yes, this can feel a lot, but it reaps benefits in the long term). Anything that took longer than five minutes goes into the log, including people dropping by with a question, lengthy text exchanges, reading reports, and meetings you attended. For the first week, just capture everything; don’t start analyzing your data yet. You want to get a realistic accounting of what you are doing without judgment. Also, try to add to your log multiple times each day instead of waiting until the end of the day (or the next day). Most of us can’t remember what we had for lunch yesterday, let alone how long we spent answering questions when someone dropped by.