The first step to integrating with your autoresponder account is to head over to the 'Account' page inside OptinLabs.
To do that, login to your account, and click on your name at the top right corner.
Click on "My Account".
Select the "Autoresponders" Tab on your account page.
Click on "Connect New Account". See below screenshot for reference.
The other tutorials in this category will help you from there on.
NOTE: It depends on the Autoresponder that you wish to integrate!