How to write emails that get replies from extremely busy people?

If you're looking to initiate a mutually beneficial, professional relationship with someone you admire, consider the email tips that work.
Don't be a salesman.
"I don't try to convince them of anything in my message," Jon Levy says. "It's not, 'Oh, I think it would be really good to do this because of X, Y, and Z.' [It's] 'This is what I do... I think what you're doing is fascinating, and I'd like to sit down with you and talk about what you're up to.'"
Keep it as short as possible.
You want the recipient to look at your message and be able to give an adequate response, even if it takes them 30 seconds on their smartphone. When Levy emails a high-demand person like a celebrity, he keeps his email down to a single sentence that cuts out any trace of filler. If he emails an executive, who makes decisions based on available information, he'll limit his message to three to five sentences and include some links they can click if they'd like to learn more about him and the Influencers.
Entice them with your subject lines.
If you're being referred by someone in their inner circle, mention their name in the subject. Levy likes the subject line "Quick Question" because it signals to the reader that they can open the email and remain on a path to a cleaner inbox.
Offer a clear next step.
If your recipient is interested in you, let them know how you'd like to move things forward by asking a question or extending an invitation to talk further.