Email marketing is one the most cost-effective online marketing solutions available. Its simplicity and speed, combined with its low cost and easy to understand reporting makes it a popular driver of business for companies of all sizes.Despite this, many marketers fail to maximize their potential from email marketing. Successful email campaigns can start by following a few rules to help avoid mistakes that could potentially damage your company’s reputation.Keep it relevantWhen individuals give you permission to add them to your email list, they do so with the understanding that they will receive relevant email marketing messages based on their previous interactions with you (e.g., a purchase, request for information, or subscription). It is imperative that you get to know your subscribers and tailor your messages to their individual needs. Irrelevant and therefore unwanted emails will damage your reputation, reduce open rates, and potentially drive recipients to unsubscribe or, worse still, mark your campaigns as spam.Remember that less is definitely moreEmail marketing campaigns are best kept short and to the point. You should try to keep any scrolling to a minimum and, through the use of clear calls to action (e.g., Buy Now or Learn More), direct recipients to your website as quickly and efficiently as possible.Consider Frequency and Timing Look at the frequency and timing of your emails. The relevancy of your campaigns will nearly always be more important than the number of messages you send. The optimum delivery time will vary depending on your target audience. For example, an email targeting a potential business client will best be delivered during working hours, while an email targeting a young mother may return more positive results if delivered later in the evening (once the kids are in bed).For subject lines, think headline newsYour subject line has the power to influence your subscribers even if they have not opened your email. People are busy and, even if they want to, may not have the opportunity to open every email you send. A good subject line will resonate with your audience and may act as a reminder to visit your website at a future point in time.Make good use of real text Make good use of real text (not graphics) at the top of your email. A graphic-heavy email will appear blank until the subscriber has selected to download the graphics. Real text in the message will remain visible even in HTML emails and will entice subscribers to open the complete email.Automate and schedule your sendsEmail marketing shouldn’t tie you to your desk. Use your email marketing software to automate and schedule email campaigns to reach your lists at a time that best suits your subscribers.Get socialTo encourage your subscribers to socialize your email content and to share your email marketing messages via their social networks, add social media sharing buttons to your emails and landing pages. It is also a good idea to publish your email campaigns directly to your own social networks.Test, test, testYou might already consider your email marketing to be pretty successful, but that doesn’t mean it couldn’t be better. Take time to split test your subject lines, designs, frequency, time of send, etc. It’s important to test one component of your campaign (e.g., subject line or time of day) per test, and make a note of your findings, so you can incorporate them into future email campaigns.