This tool transforms multiple curves into customizable stitch lines. It fits perfectly to the surface and gives you controls for scale, shape and number of stitches per stroke.

You can connect the curves ends to make your life easier.

It's very simple to use;

you just need to append the "stitch.blend" to your scene,

select the "stitch" inside the "NodeTree" folder,

add a Geometry Node to a curve,

load the Stitch on the Geometry Node,

select a surface,

enter in edit mode with the curve selected,

delete the unwanted geometry,

set the depth to "Surface"

and start drawning.