How to put the registration pop up to my own site

Hello. I have made a site that i like that show what people can get to be my member. I have become member buttons but if i link them to the registration page, the registration page comes up and they are have to click on another button there to get the pop up for registraton. is it possible to link my button to the popup for registration? I tried to take the button link from registration page to my buttons, but then it didn`t go as a pop up. :slight_smile:
You can see here if you like. http://www.outofthebox.no/medlemskap
The "code" to se the site is: lillemy
That is not a secret code its just so most people cant come in while im building it :slight_smile:
Thank you!! :slight_smile: