Check your e-mail inbox. Now, check your trash folder.

How many of those messages did you toss into the virtual wastebasket, unopened, without a second thought?

E-mail has become a cheap and nearly ubiquitous form of marketing, but that doesn’t mean it’s easy. Done right, e-mail can be the “single most important connection opportunity in existence,” says marketing consultant and best-selling author Jay Baer.

Done wrong, well, you know what happens then: nothing. So how can you strengthen your message, and engage your recipients more, ultimately leading to increased sales? Follow these tips.

Avoid rush hour. Send your e-mails midday or later in the afternoon to stand out. Your message is more likely to be deleted if it’s among that big batch of new e-mails checked first thing in the morning. “Don’t fall into the ‘delete trap’,” says Baer about the morning glut of e-mails.

Don’t waste your subject line. If you don’t tell readers what the e-mail is about and why they should care right away, it’s likely to go straight into the trash. “The subject line has to be very strong,” says David Blaise, owner of Blaise Drake & Co., an industry consultancy. Subject lines that are too cute, lengthy or misleading can inhibit readers from opening, or even worse, annoy them if they do.

Punctuate strategically. Sometimes, a question mark or an ellipsis at the end of the subject line generates the curiosity needed to get your e-mail opened. “It could be a question like: Three promotions that get people to trade shows? If they want to know more about it, they’ll open the email,” says Blaise. Just make sure the question is something your customer would want answered.

Customize your message. Generic e-mails that aren’t relevant to a customer’s interests are a waste of time both for you and that customer. For better results, tailor your e-mail blasts to smaller groups with specific needs. “I’ve been able to spend more time doing the research for each group and trying to hit the nail on the head with those individuals,” says Dave Roose, owner of Proforma Prana, “vs. throwing everything against the wall and whatever sticks, I go pick up.”

Guide the next step. Once you know whom you’re sending the e-mail to, it’s important to figure out exactly what you want to have happen next. Do you want the reader to visit your site, call your company or watch a video? Not having a clear goal is one of the most common problems with marketing e-mails. “You need to know what you want them to do, and every word needs to lead them to that conclusion,” Blaise says. “Realistically, if we don’t know what it is we want to say to someone or want them to do, we probably should not be e-mailing them in the first place.”