Since the wheel that tells you the settings for decorative stitches is so often missing from this wonderful old machine, I've taken one apart and scanned it. All you have to do to make your own is print out both pages, laminate them, then cut out the pieces. Use an X-acto knife to cut out the windows in the smaller circles (with the machine schematic) so the settings will show through, and attach them at center.
To download the scans, copy this URL into your browser, then save the document to your computer:
http://www.necchilady.com/NecchiJuliaStitchWhl.pdf
To see pictures of a beautiful Julia, go here.