The MailChimp module provides snippets to generate subscribe, unsubscribe and update forms from a MailChimp list.
After the module has been uploaded and installed it needs to be linked to your MailChimp account via your API key. To do this within the site manager go to Settings and then MailChimp and enter your MailChimp API key in the space provided.
Note: Your API key can be found within the MailChimp administrative interface by selecting Account and then API Keys.
Using the MailChimp module is as simple as placing the subscribe snippet on a document or within in a template where you wish the mailing list signup form to appear. The only the listId parameter is required and specifies which of your mailing lists the user will be subscribed to on completion of the form.