There was a time when email inboxes were spam-free. When people only received emails from people and companies they wanted to hear from. When every new email was as exciting as a handwritten letter in the mail from a friend or loved one.

That was about 20 years ago.

Since then, email inboxes have become cluttered with all sorts of junk. Even when it’s not spam per se (because much of that is now caught in spam filters), it’s often email from lists people signed up for once and never bothered to unsubscribe from.

When you open your inbox every morning, you likely spend as much time scrolling though its contents looking for something important as you do actually reading the few important things.

That makes it challenging for your business email to find its way through the morass. Hopefully you’re only emailing people who have opted-in to your communications in the first place — otherwise you’re probably spamming, which we never recommend — but that doesn’t necessarily mean the recipient is even reading your email, much less actually acting upon it.

So you have a couple of hurdles to clear, but let’s focus on the first one: getting the recipient to actually open the email and be excited to read what it contains. To do this, you need a subject line that compels those actions. Here are a few tips for how to craft a compelling subject line:

Be the subject: Maybe it’s not as memorable as “Be the ball” from the classic Caddyshack, but it’s incredibly important regardless. Put yourself in the recipient’s shoes. What would prompt you to open that email? What are the recipients’ needs? How can you fulfill those needs? What language would prompt them to immediate, can’t-wait-another-minute action?

Use verbs that prompt action: Any subject line is better if it includes a verb describing something the recipient can actually act upon: “Win a vacation for two.” “Receive a 40% discount on your first purchase.” “Meet Emmy winner Jim Parsons.” An actionable verb prompts action: opening the email and seeing what they need to do to participate.

Time-sensitive action: This follows the action-verb notion. In addition to prompting action, add a “ticking clock” that prompts action right away. “Get 50% off our premium service — only two days left” compels the reader to act right away. In action movies, the protagonist often has to face a deadline to complete a challenge or face serious consequences. The ticking clock works for the movies, and it will work for you.

Deliver in the body what you promise in the subject line: The fastest way to get your emails unsubscribed — or far worse, to be reported for spam — is to promise one thing in the subject line and deliver another in the email body. The “bait and switch” approach will only destroy your credibility and potentially get you banned by email servers. This includes offers with all sorts of strings attached; of course you’re going to want some action from the lead/customer in return for the promotion, but make it logical and straightforward.

Be sure your subject line doesn’t sound “spammy”: Terms such as “save,” “quote” and “cash” regularly trip spam filters and can send your emails into the spam folder, never to be seen at all. (How often do you check your spam folder? We don’t either.) You’re best to avoid those words or anything else that sounds like a too-good-to-be-true offer