You can create an Optin from Dashboard -> Xoptin -> Add new and click on the create button. It will ask you to select a service provider for capturing subscribers emails. Follow the steps:
- Select MailChimp from the list
- Enter the account name for your own understanding purpose.
- Enter the API key of your MailChimp account. You can find your API key from MailChimp -> click on profile picture -> Select account -> Extras you will find the API key there. Here is the direct link
- Copy the API key and paste in the API key field.
- Click on Authorize button it will automatically authenticate the API key and get the lists created in your MailChimp account
- Select the desired list for saving subscribers. If you haven’t created a list yet create one from MailChimp -> View Audiences -> Create Audience
- Hit the Save & Continue button it will create an optin and attach MailChimp data with it.