In Blade, you can easily use the Contact 7 Form with the MailChimp extension in order to use your MailChimp account in your site. By this way, you will use the tried and tested Contact 7 Form plugin in cooperation with the MailChimp one. You can find related screenshots attached to help you out.

Last but not least, Blade offers style for the subscription form you may need which you can find, use or reform on this article.