"Manage Custom Sizes" grayed out during 'Printing' a file to a PDF on my MacBook
Can someone help me ensure that my document, a custom 5.25 x 8 can be saved as a pdf? I've tried every which way I know and cannot access 'Manage Custom Sizes' nor 'Tools-->Adjust Size'. Both of which are grayed out. I can access these when I save to a jpeg. But I need an appropriately sized pdf. What am I doing wrong? Step by step would be so appreciated.
[Re-Titled by Moderator]
MacBook Pro 13″, macOS 10.15