Please expand your instructions under "Settings"

There is a large gap between your first and second bullet points that the user must navigate once he gets to his Kindle Management Page, which means he may get lost. I suggest you spell out each separate step the user must take, by replacing the current second bullet point with the following bullet points:

Click "Manage Your Devices" (in the left sidebar)
Following the lead-in, "Edit an e-mail address on ...", Click "Personal Document Settings"
Under "Approved Personal Document E-Mail List" (near the bottom of the page), Click "Add a New E-Mail Address"