Lightroom Book Module, how to create a custom Photo Text type size and offset

I used the Library module to create a title for each photo in my book, and used Auto Layout to create the book. The photo text size and Offset are not what I want. I can change this in one photo by selecting the text, then in the Text/Photo text area I can change the Offset. Likewise I can change the text size by selecting the text and using the Type area to change the Size. How can I make my own setting the default that will be created when I choose Auto Layout? Thanks! Mac OS 10.14.6 LR most recent