If you constantly find yourself wrestling with a to-do list that's longer than the Pan-American Highway (and who doesn't), then this post is for you.

Productivity experts give all sorts of tips, techniques, and hacks to get more stuff done, and most of them focus on doing things faster, so you can do more in less time.

That's all well and good. Certainly, you shouldn't spend more time doing one thing than is necessary.

But I like to step back and begin by doing something productivity experts may find revolutionary: doing fewer things.

Shorten that to-do list.

Plan to do less, not more.

Here's a formula you can follow to whittle down your daily agenda--but still get things done.

1. Delegate

Repeat after me: "I don't have to do everything myself. I shouldn't do everything myself."

If there's anything on your to-do list that you're not good at, delegate it. Find someone who can do it better (and in a shorter amount of time).

If there's anything that's not a good use of your time, delegate it. How do you know? If it's not in your Zone of Genius or your Zone of Ability, then you shouldn't be doing it.

After this step, your list should only contain tasks for you and you alone. You can shorten that list some more....

2. Defer

Does everything on your list absolutely have to be done today? Or even in the next few days? If not, then defer those tasks to a later date.

It might feel like everything needs to get done right now, but be honest with yourself. Use the urgent vs important matrix to determine which tasks you can put off without deleterious effects. Almost nothing is a live-or-die situation.

Believe it or not, at this point, you can shorten your to-do list even more.

3. Abandon

Look at every item on your agenda and ask, "Is it still important?" Some things become irrelevant pretty quickly, so don't keep burdening yourself. Again, look at your important vs urgent matrix. If something is low in both importance and urgency, then it's a good task to abandon.

If this bothers you, make a bucket list of tasks that would be "nice" to do... when you have the time. That way, it's still captured somewhere--you won't forget all about it--but it won't clutter your daily agenda and attention anymore, either.

And now, your task list is as short as it can be. You can focus on the final and most important step.

4. Do

If you've already delegated as much as you can, deferred as much as is practical, and abandoned any tasks that don't really need doing, then your list of remaining tasks is pretty well-trimmed by now.

There's only one thing left for you to do: pick one item on your to-do list and do it. Then pick another one and do that. Rinse and repeat.

When your to-do list is just a little bit bigger than you can fit into your day, the best way to be productive is to make that list manageable and do something important that you can deliver on substantially.

The more meaningful action you squeeze into today, the more time you'll start to free up in your schedule for the future-- because you've been taking care of business, your tasks are checked off your list instead of haunting you into next week and next month.

It really is that simple.

Next time you start to feel you don't have enough hours in a day, try the DDAD Formula and do more of the things that matter. Isn't that what productivity is truly about?