printing from photos

Hey there Meg Huby,

Thanks for reaching out to Apple Support Communities. I understand you want to print specific size folded cards on your Mac running macOS Mojave. I’ll be happy to help.

Take a look at this link for info on how you can create a document that has a unique size, such as an envelope or card, first see if the paper size appears in the Paper Size pop-up menu. If not, you can create your own custom paper size:

Create a custom paper size for printing on Mac

Cheers.