What does "Just swipe it and sign in the box." mean in English for Spanish?

In English for Spanish, "Just swipe it and sign in the box." means:

Sólo tiene que pasarla y firmar en el recuadro.

Listen to "Just swipe it and sign in the box.": (If you have an HTML5 enabled browser, you can listen to the native audio below)

This is a phrase that is used in the GamesForLanguage English for Spanish Language Game in the following scenes:

• English for Spanish 3, Level 3, Scene 7