Segmentation of your email list to create relevant experiences for your customers is the hard part (and well worth it for higher response and deliverability). Yet, many marketers skip over the easy part: applying a segmentation strategy to the registration process.

In other words, the best time to offer a choice of email types, content or frequency is at signup: that lets you build a larger list of engaged, active subscribers.

The first and last rule of registration is gaining permission. Regardless of which permission standard you use (double opt-in, validated opt-in, single opt-in or opt-out), it's imperative to eliminate any surprise when subscribers don't recognize what you've sent as what they thought was promised.

Surprised subscribers do not respond, and worse, they unsubscribe or report you as a spammer to ISPs, causing complaints that hamper inbox deliverability for all your email.

Be obvious about what your subscribers can expect from you-- in terms of frequency, timing, content and use of data. No matter what you plan to do, be sure to disclose it during data capture, on the confirmation/thank you page as well as in the welcome message.

And, if you are going to customize the content based on any segmentation -- subscriber-selected, data-based (e.g., demographic) or behavioral -- highlight (and celebrate) that during the registration process, as well. You'll set more clear expectations by using the language most appealing to each segment. You'll also improve conversion on your form, get more accurate data and grow your file more quickly.

Here's how it can work for you.