To get started:
Go to the Edit mode for your page, delete out the current form on that page and follow these steps:
Click to "Add New" element
Now go into BenchmarkONE and go to your Tools > Online Forms and select the form you would like to place on this page.
Choose to use the iFrame code option (Remember, this "sandboxes" the code exactly as you see it in BenchmarkONE. So do any styling you would like on the form within the "Form Style" area of the Online Form builder - including injecting your own CSS using the "preferences" option)
Copy/paste this code into the HTML box within Instapage
Remember. You will NOT see the correct display of this code until you click to preview your page