This tutorial should help you with placing our SignUp box on the Landing page, that you created on your own, so u don't have to use our pre-sets.
A detailed tutorial on where and how to create your SignUp box is here.
Importing SignUp Box on the site
a) It is necessary to just save the SignUp box and copy the generated code.
b) Insert the code in the section of the page where you want your sign-up box to be.
Finalization
a) Save the page as HTML or PHP and you're done.
b) Of course, you can customize this page to achieve the best conversion rates.
IMPORTANT: The source code might not work until your page is uploaded to the server.
If you have any questions do not hesitate to contact your Key account manager.