Decofabric Markers
Uchida
$3.79
These markers are great for dark-colored fabrics. They are water-resistant when dry, and it's recommended that you heat set using an iron according to fabric guidelines. Great for kids since they are acid-free, non-toxic, and odorless.
To avoid unnecessary damages to a project, test product in an inconspicuous area first before applying it fully. Or apply it to a similar material first before using it on the actual project.