I'll have a photo taken of each family as they arrive and later print the photos and place them on the proper pages. On each page, the guests will write something to me and my fiance. How do I keep our guests from writing a book or writing so large that I won't be able to add their pic later?

Should I draw a 4x6 rectangle on each page and write "do not write" on it? Should I have 4x6 cardboard cutout that my guests can place on the page and write around? Should I have index cards for them to write on and then mount the index cards as well as the pictures later?

Any other suggestions?

Thanks!