Link in a link?

I have the following process:

1. 
   

   1st page with the following outbound link "http://ift.tt/1D3wdJW"

   
   


2. 
   

   This links to to a Sign in / Sign up button. User has to click on "Sign Up" (2nd page)

   
   


3. 
   

   Then, the user gets redirected to a 3rd page: the sign up form.

   
   


4. 
   

   Once the sign up form processed, the user gets redirected to the checkout screen depending on the URL clicked on on the 1st page.

   
   

I can only impact Page 1 and then the header and footer of page 2 as it is a 3rd party system.

What I want to achieve: when clicking on the first link on the 1st page, the user is directed to the sign up form but with the browser history of having gone through 2 links so that he gets the appropriate checkout.

So I need a link in a link...?

Thank you so much for reading this. Please comment if you have any questions, comments or idea on how I could make this work

Thanks!