Step 1:
Go to the INTEGRATIONS from the main menu.

Step 2:
Click the add button from the top right to integrate the service with your checklist.

Step 3:
Go to the MailChimp account and select Profile from the top right.
Select API Keys from Extras.
Copy API Key or CREATE a new one.

Step 4:
Name your service (Reference).
Select the MailChimp from the SELECT SERVICE dropdown.
Paste the copied API KEY from the MailChimp account then and click the SAVE button.

Step 5:

Go back to Checklist and select any Checklist by clicking Editor Link.

Step 6:
Go to Checklist Settings from the top right of the Checklist.

Step 7:
SELECT Integration from the Side menu then SELECTS your service & the list from the dropdown and click the SAVE button.

Note: When someone subscribes to your CHECKLIST, the lead will be transferred to your MailChimp account.