How do I add a text box to the cover?

To add a text box to the cover, 

- go to the dedication page (page 1)

- add a text box

- shrink down the text box so it's very small

- drag the text box down to the filmstrip at the bottom and drop it onto the "mini" page of the cover

- go to the cover and you'll see the text box

- expand the text box to its normal size