Change Text and Images
To change the text just hover over the element and use the text editor. Here you can style and change colours.
To change an image hover over and hit edit also. You can then remove or replace an image as needs be.
Hover over buttons and hit edit
Change the link by highlighting and hitting insert link
To add new elements
Use the plus icon either top over the editor or below.
In some cases you will need to add a new row and then elements. If this is the case use the large plus symbol at the top or the one below and hit row.