To some, June means the official start of those lazy days of summer, with barbeques and pickup softball games, and time spent relaxing on the patio with a favorite beverage. To many retailers, though, June is a busy month, because it's when they pick up extra revenue from those shopping for "Dads and Grads"—Father's Day and graduation season.

How do you get your share of that revenue?

Over the last few years, email marketing has proven itself as one of the most effective ways to target often-fussy shoppers. And because dads and grads can be two tough groups to shop for, the people who read your email may genuinely be looking for ideas, both traditional and unusual.

If you have a professional-looking email campaign that is well conceived and executed, you can drive customers to your store or website, and convince those who have never purchased from you to give you a try.

Let's take a look at some tips and ideas to get started.

Don't lump the two special occasions together. Dads and grads have very different needs and tastes, so plan your marketing efforts as two separate campaigns. That way in one design you can be very specific with your offer: For example, you can highlight power tools and things that dads love. Meanwhile, the Grads campaign can highlight things they'll need as they enter the next level of school or the working world—from haircuts to suit jackets to laptop computers and beyond.

Be creative. Retailers often have a lot of products relevant for dads and grads, and even service businesses (e.g., insurance, realty, and travel) can find a way to tie into the holiday or occasion. For example, insurance agents can offer a discount on car insurance for new grads.

As you refine your list of products for the campaign, think of a call-to-action that will make a good email subject line: for example, "No shipping fees for Father's Day gift purchases." Remember to avoid words in your subject line such as "free" to make sure spam filters don't reject your message.