I use Optin monster on most of the websites to capture emails. The most basic one is the exit popup- as I know many people get annoyed with pop ups. But they work.
My favorite one is the modal pop up – this means when someone clicks a button to signup (optin) to something – there is a small window that comes up for them to enter their information (normally an email address). This saves time from them having to load another webpage and reading a new sales letter and optin form.
I use the Optin Monster WordPress plugin, then I go to update the integrations. Once I update the integrations (refresh) I then to go the page I want to add the automation and then I am using this form of code:
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Which will look like this:
Where I update the data-optin-slug field. Also I am using Pro editor (X theme) so some other classes you may need to remove.