Help with my power point autograph book please

[Momma_of_three]

I have been spending hours creating autograph pages for an 8x8 photo book in power point. I started with 8x8 slides and then made all my pages on that, downsizing photos and such that I found online so they would fit on the page. Now that I am done and I download them into shutterfly in a 8x8 book it says they are low resolution. I am not sure what I can do. Any help would be greatly appreciated!

 

[Momma_of_three]

I seem to have figured it out after much trial and error. I changed my slide size to 15x15 and then re-saved everything in the best resolution the computer would let me. Thank you to all who took the time to read my post.