Use your real email signature: Just like using a real reply-to email address, you want to use real contact information within the email and the best way to do that is to include your contact details in the email signature. Giving your readers the opportunity to contact you or connect with you online is a great way to be personal and build a relationship with them.
It's important to take advantage of the window of opportunity when your company or brand is at the top of your prospects' minds. You can really get a pulse of what future engagement will look like by what people do when you email then within 24 hours of their subscribing to your newsletter, signing up for an offer, and so on. Plus, it's a great opportunity for branding and setting expectations.
Remember, data collection is a two-way street. People won't give you their data for anything. So, think about how you are managing your subscribers' expectations. How clear is it to new recipient what they are going to be receiving from you? Try and get a good a feel for the experience of the person receiving your data collection methods as you can at this point.
As long as you are keeping track of your client’s most recent appointment times, this kind of automated reminder email is quite easy to set up. Use a custom date field to record when their last appointment time was, then set up the email to be sent 3 months later (or whatever your recurring schedule is) to remind them that they are due for their next appointment.
The downside of just making offers is that they’re not useful on their own. People on your list won’t receive any value from you unless they buy what you’re promoting, so they have little reason to stay subscribed. That’s why this email marketing strategy doesn’t work alone. And it’s why many e-commerce sites struggle to keep people interested. There are a few exceptions (e.g., Groupon) that rely entirely on making offers—but then the reason people joined the list was specifically to receive those offers.