After two decades leading several startups through fundraises and other top priorities, I've learned a prioritization hack that every startup leader should use to tackle a single mission-critical task without letting the rest of the business fall apart.

The hack comes in handy around fundraising, because when you're a startup CEO, you're always balancing two seemingly incongruent priorities: You can raise money, or you can grow, but you can't do both at the same time.

Raising money is a long, difficult process, and also full of rejection. It's physically and mentally exhausting -- and any serious fundraise will take at least six months of effort from first investor contact to the final close. At least.

It begs the question: How do startup CEOs raise money without company growth falling off a cliff? It's one of those startup Catch-22s. 

Startup CEOs in particular bear the additional burden of having to wear multiple functional hats on top of their traditional executive role. So when a startup CEO faces the prospect of a single critical priority absorbing all of their available time--whether it's raising money, boosting sales, or hiring talent -- many functional areas of the company suffer as a result.

Or do they?

Committing to a Single Top Priority

Every startup leader -- in fact, usually every startup employee -- has at least a dozen "top" priorities at any given time. It's a phenomenon that those fake advice peddlers will say you need to eliminate at all costs. 

"Focus on one thing at a time, all the time," they'll preach.

Sounds great, right? Makes for a nice motivational poster. But any startup leader who has actually led something to success will tell you that advice is totally unrealistic. In fact, if you do have a single top priority all the time, you're more likely stuck in a functional middle-seniority position at a large company. And you're likely bored out of your mind.

Like most questions that arise from various startup Catch-22s, the answer is one of those CEO secrets that's not really a secret -- in that it's not simple enough to put on a motivational poster, but it's not complex enough that you can write a best-selling self-published e-book about it.

Look, once you pick the initiative you're going to commit to, there are four basic rules to guide you through getting it done without sacrificing the rest of your business -- or your personal life.

Rule 1: Set a time frame and stick to it

This sounds easy enough, which is probably why it's rarely adhered to. You need to set a clear time frame that can fit into your quarterly or annual schedule with as little disruption as possible.

I just completed a 30-day period with one single focus. During those 30 days, and only those 30 days, it was the first thing I addressed every morning, the thing I weighed against all my other daily commitments, and the last thing I thought about at night.

At the onset, I let everyone who mattered know that this would be the primary thing I was focused on, and if other commitments had to be pushed back, this was why. Doing that not only saved hours of explanation turning down requests for my time, it probably also cut the number of those requests in half.

When my 30 days were up, I was at about 95 percent of my goal for the thing. But that was fine, because I had a plan.

Rule 2: Map out a disentanglement plan

The biggest mistake leaders make when focusing on a single top priority is bailing out before the period is up. The second biggest mistake leaders make is going longer than they said they would. This happens when they don't reach their goal in time, so they keep the time frame running indefinitely, and the rest of the business suffers.

To avoid both of these mistakes, you need to establish a disentanglement plan at about 90 percent of the way through your original time frame. This means if your time frame was six months, which is 180 days, pick a day 18 days before the end, and on that day, stop, assess where you are, compare against where you wanted to be, and figure out how to address any shortcomings once the period is over and the priority is no longer your sole focus.

When your 180 days end, the priority can still be your second focus or your third focus or be no focus at all. Do what you need to do to hit your goal, but understand that your commitment to it is about to drop way off as you get your mind back into all those other priorities you've been ignoring.

Rule 3: Don't say back burner

I'm not a fan of the term "back burner" to describe the rest of the tasks that aren't the top priority, because it implies that everything else is either still a priority or not a priority at all. Again, in the real world, this just isn't realistic, because the only way your top priority will remain your top priority is if you prioritize everything below it.

Yes, as a leader, you still need to pay attention to what's going on around you, fix problems when they arise, and give direction when it's missing. So you'll have to draw a line between which tasks and initiatives will still get some focus and which will get zero focus. Then, for those that remain in focus, you'll have to draw a line at how much focus.

A benefit is there will almost always be a few tasks that you'll realize don't need your focus at all. Leaders tend to build up time wasters like coders build up technical debt.

Rule 4: Delegate and drop

Once you've made your decisions about which tasks and initiatives still need your focus and which do not, drop as much of your hands-on involvement in them as possible and delegate the rest.

When managing priorities, the key isn't to "forget" about the lower priority items, it's to manage them. And management means just that; letting someone else execute while you supervise.

This can be difficult for most leaders, so think of it this way: If you can't drop a task you know you need to drop, you've got a habit you need to break. If you can't delegate a task that needs to be delegated, you've got a resource you don't trust.

Fix both of those problems before you embark on your single-focus period. Otherwise, you'll get sucked right back in, one way or the other.