Change Header Of Subscription Form

Hi guys,

I tried to get into the documentation – however, was not able to figure it out by myself.
It’s a simple question: I created a page with the shortcode: [newsletter]. Now the page displays a very small form with the Header “Newsletter” a small box to insert your email and a button to “subscribe”. I would like to change the header from “Newsletter” to something else. How to I go about redesigning this?
I get confused with all the different options for widget designs, shortcodes, etc.

Thanks guys for the help!

https://wordpress.org/plugins/newsletter/