Part of being a successful email marketer is planning. You don't just see the month before you; you see the next month or two (in some cases, the whole year ahead). You know what months are your busiest and which ones require extra hard work.

Some months, like those in the holiday season, require extra planning because of the deluge of competition in your subscribers' inboxes.

If you need help preparing for the holiday season (which isn't as far off as you think), the Email Marketing Holiday Calendar by ExactTarget offers planning tips for July through December.

For example, though the back-to-school season dominates August and September, you can start reminding folks about the upcoming holidays. Encourage folks to sign up for credit cards or to download your mobile app in preparation for their holiday shopping.

In October, the average amount of promotional emails that retailers send to active subscribers jumps to 20 emails from August/September's 18. So, you'll need to focus on making your email messages stand out from your subscribers' increasingly hectic inboxes.

Ideas for October email themes include taking advantage of pre-holiday clearance sales, pre-ordering the hottest gifts, creating wish lists, and learning about financial services and layaways.

Get more tips for planning your email marketing through the holiday season by checking out the following infographic: