What are the keys for writing cold email to prospective employers?

​Despite the gray area of a cold email's effectiveness, it's still one of the most helpful ways to get the job you want. Like most job advice, the key to the cold email is to own it like you've been doing it your whole life.
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That is, you need confidence in your tone, even if you've failed before. Check out these seven tips to find out how you can write the most effective cold email possible.

​1. Know something about the person you're emailing.
Everyone's heard the job interview version of this tip: Always research the company where you're interviewing. The same applies when sending a cold email, so make sure you know the recipient's job title, what he/she does in his/her position and a little bit about his/her background.
If you have something in common, highlight that connection (e.g., "I also came to journalism from the publishing industry").
 
2. Use a specific subject line.
If you're cold-emailing someone, it's likely that person is busy and receives numerous emails per day, including other cold emails. That's why a short, snappy and informative subject line is more important than ever.

3. Don't hesitate to show that you're passionate.
A cold email is a first impression, just like the first few minutes of a job interview. A cold email that's, well, cold won't do you any good. If you feel strongly about the field you work in, don't hesitate to show that you're passionate about it.

4. Keep it short and direct — don't explain yourself too much.
Be passionate, but don't give your life story. The reason you're emailing should be apparent in the first paragraph, whether you're interviewing for a position or just starting a formal relationship. As a rule, a cold email shouldn't be more than a few paragraphs, and those paragraphs should be short.

5. If possible, show the work you've done.
You're more likely to get a response from a cold email if the recipient knows you're serious about pursuing your career of choice, and the best way to express that is to show your work.
Send along a streamlined portfolio or a link to your website if you have these, as well as links to social media and blogs — if they're professional. These are great things to include in your email signature.

6. Proofread.
There's more pressure on a cold email than an ordinary email because it will be scrutinized (just like a cover letter). Make sure it's flawless. Carefully proofread for typos or sloppy writing, because you can't unsend that email.

7. Follow up in a productive way.
If you don't get a reply right away, wait about a week before sending up a follow-up email, especially if you know that the person you contacted is busy.
 
When you do follow up, rather than harping on information you already gave, ask if he/she saw the first email and reiterate that you'd love to talk whenever he or she finds the time.

A few more details can be found in this article.