Click on the button to add a caption box to a page.
If you're working on a double-page spread, you will be presented with the choice to add a caption to the left page or to the right page.
The caption box and tools menu appear on the selected page, as shown below.
To enter your text, click inside the caption box and type your desired text.
The caption tools allow you to edit the font style, size, color, alignment and text formatting just as in a word processor. You can highlight a portion of the text and change its formatting and color without affecting the entire text in the box.
To resize a caption box, simply click on one of its handles, as depicted below.
Bring caption forward/backward. Used when multiple design elements are on the page
Pressing this button will remove the caption from the page
Change the background color of the text
Zoom in on text (example below)