I delete 1,000 unread emails a day. Here's how I weed through messages and got over the anxiety of missing an important one.

• Diana Lee, the CEO of Constellation, an adtech company, oversees a team of 125 employees.
• She says that on an average day she receives and deletes 1,000 emails.

This as-told-to essay is based on a conversation with Diana Lee, the CEO and cofounder of Constellation, a software-as-a-service marketing platform, who's based in New York City. The following has been edited for length and clarity.

As the CEO and cofounder of a multimillion-dollar adtech company, I work with Fortune 500 clients in highly regulated industries including pharma, banking, and automotive — so I get a lot of emails.

On a typical day, I receive more than 1,200 emails. I'll often delete 1,000 emails a day, mostly from sales representatives, vendors, and lenders.

I immediately delete any emails that aren't addressed to me or don't say 'urgent' or 'timely' in the subject line

I believe that if the subject or first line in the email body isn't personalized, then it's not worth my time or energy and is likely a mass spam message.

I'm on all client and internal aliases, which tend to contribute to a majority of my daily emails. When it comes to internal or client emails, if I'm not the only person on the chain, then I automatically delete them because I have confidence that my team will get back to the person. Anyone I'm in constant communication with knows to clarify in the subject line if they need my assistance or input on something.

If you want to get my attention, personalize the email and show how you're going to benefit me

A ton of emails only focus on what they can do in general — but to have any value to me, it should be centered around what you can do for Constellation. Those are the types of emails that make me interested in learning more, and I forward to the right internal team member.

If the email is addressed to me and if I'm the only one on the chain, then I read through the email to determine if it's something I need to handle or forward to the appropriate person. If I'm the only person on the chain, you can be assured you're getting an immediate response.

One of the first things I do in the morning is scan my inbox for emails that may have come in from clients in different time zones

I find it easier to set aside dedicated time to do this, so I usually wake up early — between 6 and 7 a.m. — to focus on organizing my inbox. I'm usually running in and out of meetings or have lengthy conference calls throughout the day, so I only address emails that are urgent and delete the remaining.

I like to handle my own inbox so I can stay plugged into what's happening across clients and internally, so I don't have anyone checking my emails — but I do have someone who assists with my scheduling.

If an email requires my attention and will take under 10 minutes to handle, then I like to address it right away to cross it off my list and not have to worry about it later. If it's something that will take more time, I leave it as unread or mark it as "important" so I know to come back to it later. For these circumstances, I tend to block off time on my calendar between meetings to review all at once.

I'm able to delete this much email easily thanks to my trust in my team

Constellation currently has 125 employees, and despite so many other tech companies downsizing, we're projected to reach 185 employees by the end of 2022. I have 10 direct reports.

Being able to rely on my employees is crucial to the success that Constellation has seen over the past few years. I know that my team is able to handle anything urgent or bring the issue directly to me if necessary.

There are various team members I rely on, but my trust is in the client leads to either respond themselves or make sure that someone else on the team does. It's rarely the case that I would need to be the one to address team or client emails because of the way we structure teams at Constellation. We've created a "flatish" organization so there are multiple employees per team who are equipped to answer any and all client questions.

I play a strong role in hiring and like to build a relationship with each employee, which also plays a huge part in reducing my anxiety around emails

Knowing employees and being able to place a face with a name puts me at ease and instills confidence in them. Using this strategy, I've rarely missed an important email, and when I have, my team loops me back in.

As any founder can relate, I was much more hands-on when we first started the company, so I needed to be in all communications to help establish trust with our clients. Now that I can delete a majority of those emails, I'm able to focus more time on new business opportunities as well as internal and external strategies that not only benefit Constellation but also our employees.

To get comfortable with deleting large amounts of email, a good starting strategy is determining a system for sorting and scanning

As a founder, you wear many hats and have a lot of responsibilities, so you want to be utilizing your time in the most effective way. If you have the resources, hire someone specifically dedicated to scanning and organizing your inbox.

Another strategy is setting aside time to review emails. That time can be spread out across the day or in a big chunk in the morning and at the end of the day. Having structure will help you get into a rhythm and reduce stress around constantly needing to read emails.