PICS: Kate Middleton Spends 4 Hours at Fave Salon

After being absent from the spotlight for a few weeks, Duchess Kate stepped out at her friends' Wiltshire wedding on Saturday where she and younger sis Pippa Middleton nearly stole the show with their glammed-up ensembles.

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Like clockwork, Kate's hair looked especially glossy and fresh underneath her red fascinator, which matched her scarlet lace Collette Dinnigan knee-length dress. And it's no wonder her brunette strands looked so gorgeous -- she had just spent four hours at the salon Friday!

The 29-year-old royal stopped by her go-to hair haven, Richard Ward Hair and Metrospa, in London's stylish Chelsea neighborhood where she sat all afternoon for a series of services including getting her hair colored with an organic vegetable-based hair dye.

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An insider tells Us Weekly that "Kate goes in for a long appointment about every eight weeks. The shorter appointments for trims and treatments aren't always done in the salon, but she doesn't want to stop visiting the salon for her longer appointments. She loves her time there and she has known everyone there for years so it's really relaxing for her."

Kate, Pippa and their mother Carol Middleton have been trusting the salon's tress masters Richard Ward and James Pryce for over eight years. (Pryce created Kate's hairstyles for her April 29th wedding day and accompanied her on her North American tour in July.)

Earlier this summer, Ward told Us the trick to creating the princess-in-training's picture-perfect blowout.

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"To create the natural Chelsea blow-dry, apply a holding serum onto wet hair to take out the frizz and make the hair silky smooth. Start with hair that's 80 percent wet and use a good blow dryer with a concentrator nozzle and a real-bristle brush. The serum memorizes the form and holds the curl in place while you blow dry."

"Anyone with long hair should have it trimmed regularly," he added. "Also get a deep conditioning treatment every six weeks or so to keep it healthy. I like our Richard Ward Couture Hair Silk Protein Masque."