1) Adopt A Clean Email List: no one enjoys duplicated messages, even as text messages, you will not enjoy seeing repeated text in the phone. The same applies to your subscribers, they won't like to see the same messages duplicated in the email boxes.

• Issues can arise leading to duplication of email addresses, and a subscriber will get a particular email more than once. This can result in users signing out of your list. Identifying these emails and doing a clean up is crucial to the business. Although most email marketing platform will automatically clean up your list for you. In cases where your system fails or you have the same individual with 2 or more email addresses. You will have to stream it down to one email per each person on your list. A good ESP will definitely take care of this for you, but I think it is important you take note of it too as you work on.
• Avoid wrong Email Addresses: Wrong email addresses will never be delivered, rather they will give you a poor reputation and your email bounce rate will increase. Although ESPs will remove them, but good you take note of these two major issues:

a) Avoid buying email addresses: purchasing email addresses of people who never opted in to your email list is a waste of time and money. Most of the time, the email list sold is full of garbage for the trash bin. Do it the right way, build your list.

b) Adhere to the double opt-in technique: Email confirmation from your subscribers is a good way to ensure you have the correct email address. Apart from gathering correct emails, you are sure your subscribers are interested in your product or services. Thus you have subscribers that will convert to customers.