Need to add a button

Hi,

I am a manager of the AU/NTL Association Groupsite and we would like to modify our application process by adding some information about our site and allowing applicants to pay membership dues.  To do this, I'm thinking about adding a new page just after the application and I would like to add a custom "Contribute" button to the page.  I need the button to link to the Contribute section we already have in our menu options. 

I have explored and don't see a way to do this.  Can someone help, please?  Thank you!