Artwork Guidelines

If you mean Artwork that's works with an Auto Digitizing Feature of any Digitizing Software Program so you can use the Automatic Feature/Tool to Convert the Artwork to an Embroidery Stitch File, then here's the tip: CRAYON drawn Artwork.

Yep, you need THICK Clean Lines like those used in Coloring Books for an auto digitizing convert to embroidery stitch file feature to work correctly.

Small details, thin lines, etc. will never convert correctly, no matter how expensive the digitizing software is or no matter how tallented the Artist is that created the artwork.

Clean Vector Images are your best option that I'm aware of.

Manually punching/digitizing design is ALWAYS better than ANY/ALL auto digitizing conversion.
Old School Skill still RULES if you want a production ready sew out, with excellent registration, sew out without puckering, attractive stitch types, lengths, styles, small details, branching, least amount of stops, color changes, etc. etc. etc.

NO AUTO DIGITIZER Feature/Tool in any software program produces quality production designs.

It would be helpful for her to study different embroidered designs while taking note of the various design elements and how they are rendered in thread. She’ll want to familiarize herself with the three basic types of stitches, satin, fill and running, and when these types of stitches are used. She should also be aware of how stitch type, length and direction can affect the look of the thread color. Many printed designs must be simplified for embroidery. Elements like fine lines and shadows and gradients must often be eliminated. Embroidered elements that can’t be connected by a connector thread must be trimmed and each trim involves a tie-off/ lock stitch which can negatively affect the look if the element if the item is small (a small star). This is especially important when embroidering text. Text that is kerned so that each letter is connected won’t have a trim/lock at the end and start of each letter so it will look better and embroider quicker with fewer problems than text that is spaced.