While the new Apple Watch Series 3 looks virtually identical to Series 2, the cellular models feature a red Digital Crown.
Fortunately, for those who plan on upgrading but don't like the color choice, it can easily be changed with WatchDots.
WatchDots are tiny, vinyl stickers that cover the Digital Crown and Side button. They're available in a wide variety of colors, including white, black, midnight blue, yellow, orange, gold, sport green, sport blue, sport pink, fog, walnut, antique white, magenta, and other band-matching options.
MacRumors editor Juli Clover reviewed WatchDots a few years ago and was generally positive about the way they looked and held up:
My WatchDots have been on my Apple Watch for about two weeks now and they're looking as good as new. There's been no peeling, even when my watch has gotten wet, and using the Digital Crown and side button a lot hasn't affected them. Since this is a review, I put on and removed several sets of WatchDots, and I can safely say they're not going to cause any damage to your watch. You can peel them right off with a fingernail, but like most vinyl stickers, they're not reusable.
She did experience some residue left behind once, several months after removing the WatchDots, but your mileage may vary.
WatchDots come in sets of three for $9.99, with free shipping within the United States.