You say “new red book,” and yes, there is a rule. It’s called the Royal Order of Adjectives—an imperious name for an ordering system. The list below begins with adjectives placed farthest away from the noun (Determiners) to those placed nearest to the noun (Specifiers).
Determiners: Which one (the, a, an, my, her, this, that, these, those). Most singular nouns in English are preceded by either an article, a possessive noun or adjective, or a demonstrative adjective. Plural nouns do not use “a” and “an” but may use the other determiners.
Subjective description: (slow, ugly, easy, delicious) These adjectives can be considered opinions of the speaker or writer.
Size: (large, small, three-inch-long, two-liter) The hyphens are used to create words that don’t exist in English. Notice that every adjective is singular (three-inch, not three-inches) even if the word it describes is plural.
Shape: (round, misshapen, skinny, elongated)
Age: (new, antique, fifty-year-old) Notice that the adjective “fifty-year-old” does not put an “s” on year because all adjectives are singular. “My fifty-year-old brother” but “My brother is fifty years old.”
Color: (red, striped, mottled)
Nationality: (American, Asian, Indian)
Material: (cardboard, polyester, paper, metal)
Specifier: (rocking [chair], player [piano], Apple [iPhone])
Related to this idea of ordering adjectives is the question of which ones need commas to separate them. The rule is that if the adjectives fall into the same category (both colors, for example), then use a comma. If the adjectives come from different categories, no comma is necessary.
Correct: My successful tall, willowy Korean sister travels often.
Most Americans cannot explain the rule of ordering adjectives. If they have heard the adjectives ordered correctly as children, they use that same order. They go by what sounds right, but they cannot explain it. ESL students who have not heard adjectives ordered a particular way may not know there is an order, and may order the adjectives arbitrarily. It is important for teachers and parents to point out to ESL students that there is a correct order.
Even preschoolers can be told to say “a new red bike, with the color red right next to the bike” so that they become aware that there is a right way to order words. Little children often use size and color to describe an item, so it is important to point out that size comes first, then color.
Some Americans put commas between all adjectives preceding a noun, and others don’t use any commas. More and more the practice in the U.S. is not to use commas unless leaving them out leads to confusion.
Try this quiz to see if you understand the Royal Order of Adjectives: