There are various types of controls that you can implement in your email marketing strategy:
Unsubscribe Links: This is the most basic form of control. Make sure it is easy to find and functional. Preference Centers: Allow users to choose the types of emails they wish to receive, such as newsletters, promotions, or updates. Frequency Settings: Give subscribers the option to choose how often they receive emails from you. Content Customization: Let subscribers select topics or types of content they are interested in.