Inboxes are increasingly cluttered. You know that. Yours is.

So how can you make sure your emails actually get opened and read?

Good question, and one that Ollie Roddy, a marketing assistant at sales-i, set out to answer. (Check out the full -- and free -- white paper.)

Here’s Ollie:

Let's start with some telling statistics:

  • Email opens increase after 12 noon., with the most active period being between 2 p.m. and 5 p.m. (MailChimp)
  • 76 percent of email opens occur in the first two days after an email is sent. (Alchemy Worx)
  • Emails on a Tuesday have higher open rates than emails sent on any other day. (Experian)
  • Subject lines with more than 3 words experience a drop in open rate by over 60 percent. (ContactMonkey)
  • B2B customers have become desensitized to words such as "reports", "forecasts," and "intelligence." (Adestra)
  • Email marketing has an ROI of 4,300 percent. (Direct Marketing Association)
  • When it comes to emails, the average adult attention span is down to 8 seconds, which is less than that of a goldfish. (Entrepreneur)

So, what should you do?

Leave the bait to the fishermen.

The folks at Copyblogger believe that 80 percent of an article's success lies in the title alone, and it does make sense: if the title isn't strong, how can you expect anyone to click on it? Unsurprisingly the same rule applies to your emails.

But it's also important not to become a click-baiter with your subject lines. Remember, it's one thing to write subject lines that get your emails opened, but it's another to write subject lines -- and emails -- that gain trust.

When writing subject lines, you're ultimately judged on how well you engage, or interact, or even sell as a result of your emails... and not on how many emails you manage to get opened.

That's not to say that subject lines aren't important, because according to Convince and Convert, 33 percent of email recipients open emails based on the subject line alone. There are a lot of tricks of the trade which, when applied correctly, can be used to get more people to open your emails.

Here are the best.

You had me at "Hello [name]," ...

Subject lines including the recipient's first name have higher open rates than unpersonalized emails, according to Retention Science, but using a name in the subject line can be risky.

First, it can quite easily go wrong; accidentally spelling Martyn as Martin, Lucie and Lucy, or Shaun as Sean can ensure you aren't taken seriously.

Similarly, if you're automating your emails and sending them en masse and have bad or poorly entered data, people could receive emails with greetings that read "Hello [COMPANY NAME]" or "Hi ." This makes you seem spammy and turns people off your company straightaway.

As a general rule, don't call someone by their first name in a subject line or email until you've spoken a few times and are actually on a first name basis. And, when you do finally lead with their first name, make sure you double-check the spelling.

To "RE:" or not to "RE:"? That is the question.

Contact Monkey recently tested numerous different styles of subject line for open-rate success. They found that the five most clicked-on subject lines all included "RE:" at the start.

So should you start using "RE:" at the start of all of your emails? Of course not. Sneaky salespeople use "RE:" to make it seem like they've spoken to you before. It's an awful start to any business relationship.

Your open rates could be at 100 percent because you use "RE:" at the start of every email you send, but who cares if nobody trusts what's written inside?

Do things the proper way: there's no need to trick people into opening if there's genuine value in what you've got to say; while you need to make sure that your subject line is clickable, you also need to make sure it's honest. Reserve the "RE:" for replies and let your honesty do the work.

Size matters. A lot.

Contact Monkey found that the best performing subject lines have one to three words. What's more, most email clients give you a preview of an email next to the subject line, which many people use to decide whether or not to open.

This makes your first two lines (subject included) the most important of your email, so you need to use them to let people know exactly what you're getting in touch for.

As a rule of thumb, put the most important things right at the start of your email and go in depth with the minor details throughout. You can't expect people to remember everything they read, so give them the most important information straightaway.

Also, with regards to using the message preview to entice people into clicking, think about asking a question, talking about a benefit of your product/ service, or making a really bold statement that confuses them and creates intrigue.

Any rapport-building questions about recent holidays, golf trips, or birthday celebrations are important, but can always go right at the end of an email, as they serve to prompt a response.

Think mobile.

An astounding 53 percent of emails are now read on mobile phones. It's incredibly important to remember a mobile screen on average shows only four to seven words in the subject line, so bear this in mind when crafting your subject line. (That could be why subject lines with only one to three words are the most successful.)

And this trend might become even more important if smart watches become as popular as smart phones have, since they're unlikely to show more like three to five words.

While it's not always possible to stick to this limit, it should at least be considered when writing an important email you want to be opened and read.

"Contestant, let's see what you could win... "

Generally speaking, the first thing peopele ask themselves when looking at an email is: "What's in it for me?" If the subject or first line tells the reader what they'll get by following through on the call to action, they're not only more likely to open the email, but also to search within and find out what they need to do to get the "prize."

Everything you've just read is pointless and irrelevant.

Pointless and irrelevant, that is, if your email doesn't even make it through your customer or prospect's spam filter.

Think of yourself as Superman or Superwoman (minus the external underwear -- not a good look) and of spam filters as Kryptonite: the only thing that can stop you on your quest to improve your email open rates and make more money.

There are specific words that should be avoided at all costs if you want to beat the virtual gatekeeper, and you can see a full list of them here.