The simple version is that anything for children 12 and under must be labeled, clothing or product. ALL clothing of anykind any size, must be labeled.
Label must contain store name, city, state, country, fiber content, laundry instructions, Date of manufacture DOM, and item # in case of recall.
It has been said the fine for not labeling correctly is $11,000. I'd rather be safe than sorry, so my labels have all that on it.
Labels must be fabric,printed, not iron on printing, and sewn into the item. If it is a garment, there are specific places it must be sewn.
I make my own labels, 1/5 x 3" with my computer and cotton fabric or twill ribbon. Easy peasy, el cheapo.