Your heroine is wearing a red gown to the ball. Instead you could say her gown was scarlet. See how much stronger that word is?
Your hero is wearing a black suit. Instead you could say his suit is ebony. Ebony is more than just black. It is a deep, resplendent black.
Here are a few sentences taken from my historical romance 'Surrender the Wind', where I do not use the formal color word.
His waistcoat and linen shirt were blotched with crimson, the right sleeve torn at the seam.
Instead of saying his clothing was blotched with blood or using the word red, the use of 'crimson' gives the reader a word that paints the picture in the reader's mind of a wound, of both the noun and a word describing it. Crimson is a deeper red, dark and adds an ominous feel to the narrative.
At an hour when the light of day painted the sky magenta, a man on horseback rode through the gates of Ten Width.
Some writers might not use a color word in this sentence at all. But you ask the question how did the light of day paint the sky? The word 'magenta' presents the image of a sunrise. Magenta is a soothing color, a rich purplish red. And if you want your scene to express that kind of mood the use of this color fits it.
Liquid gold edged the clouds.
The writer could say 'yellow edged the clouds', and that is fine. But think for a moment what a cloud looks like when the sun is behind it and has either a gold or silver lining. Beautiful, right? So why not paint that same image in your reader's mind? Gold is a warm or hot color.
Here is a simple color list that might help.
RED - Burgundy, Rouge, Magenta, Maroon, Scarlet, Garnet, Crimson, Claret, Vermilion, Wine, Ruby, Fuchsia.
WHITE - Eggshell, Ivory, Alabaster, Pearl.
YELLOW - Topaz, Canary, Honey, Maize, Amber, Gold.
BEIGE - Bisque, Taupe, Sand, Shell, Fawn, Buff.
BLACK: Onyx, Jet, Charcoal , Ebony, Raven.
BLUE - Navy, Cobalt, Sapphire, Slate, Teal, Turquoise, Aqua.
BROWN - Copper, Bronze, Burnt umber, Nutmeg, Cocoa, Chocolate, Chestnut.
GRAY: Charcoal, Slate, Ash, Smoke, Pewter.
GREEN - Jade, Chartreuse, Olive, Shamrock, Emerald, Moss.
PURPLE - Lavender, Amethyst, Violet, Plum, Mulberry.
ORANGE - Coral, Salmon, Copper, Melon.
In the comment section, tell us what colors you would use to describe the following gowns.