I write the Scott number and any other descriptive text I need using MS Word.
I then print that on my inkjet printer, using AVERY #18665 clear, full sheet (8½x11) label stock.
I cut the printed sheet into the appropriate size and place the label on the blank page as needed.
Scott albums include the appropriate number in each space provided, but they are covered once the stamp is mounted, and as we all know, stamps are not always in numerical order on Scott pages - especially plate block albums. So, I used the process to add visible Scott numbers to every stamp and plate block in all of my Scott National and Plate block albums. Yes, it was very time consuming (and educational), but the final result is well worth it. No more guessing at Scott numbers.
Here are two examples of that:

