Even the most organized to-do lists can be overwhelming if you don't know where to start. 
Luckily, Edward G. Brown lays out a simple solution for prioritizing tasks in his book "The Time Bandit Solution: Recovering Stolen Time You Never Knew You Had." All you have to do is differentiate between what's most important — the "critical few," as Brown puts it — versus what can wait — the "minor many."
At the core of this decision process sits the classic 80/20 rule: You should dedicate 80% of your time to the 20% of tasks that prove most profitable. "Not everything we do is of equal importance, no matter how it feels when our entire to-do list is racing around our brain," Brown says.   
To determine your critical few and minor many, Brown suggests creating an "Importance v. Urgency Prioritization Grid." This reorganizes your to-do list so that it's sorted by urgency. Start by making a grid with four boxes. Label the two columns along the top as tasks that are extremely important to you and tasks that are only somewhat important.
Next, label the two rows along the left to represent tasks that are extremely important and somewhat important to others.
Here's our version of Brown's prioritization grid:
How to make the most of your time
Mike Nudelman
Your critical few are the tasks that fall into the A1 box on the grid, Brown says. These tasks are important both to you and those counting on you, so they should be given top priority. "You have to learn to prioritize and admit to yourself what you probably already know: What's urgent you cannot live without; what's important you have to deal with but not at the expense of what's urgent," Brown advises. 
Once you complete the projects in A1, move on to A2 and B1. You might need to adjust which items belong in your critical few box as deadlines near, Brown warns. 
Differentiating between tasks that are important to both you and a client or boss versus things that are only important to someone else will allow you to make the most of your time. "This is you training yourself to take situational control over your time based on knowing when something isn't really urgent," Brown says. 
Though it may seem counterintuitive at first to not help someone the minute they ask, in the long run you'll save yourself time — and stress — by getting your most crucial tasks completed first.