Anonymous“Are there specific rules that I can memorize?”
No. Each case is separate from the others and will have to be learned separately. Modification with a noun or a "normal" adjective is most common; modification with an
-ing form is less used. At least that's my impression.
Very often the -ing form is used when the -ing form indicates an activity of some kind -- things that people spend time doing.
fishing tackle/gear
cooking utensils
coloring books
knitting needles
reading materials; writing materials
singing lessons
But there are, of course, many other ways that the -ing comes into play, so no general rule can be given.
CJ