Saturday night Cheryl sat at the judges' desk with glossy hair that had been expertly blow-dried; it was more brunette than red and a good few inches shorter than usual. It was also a far less wag-ish and try-hard hairstyle than she has sported in recent weeks. Case in point: last week her hair extensions were far too long and straight, and a fortnight ago she showed off a Princess Leia-esque hairstyle that just didn't work, proving when it comes to hair, sometimes, less really is more.

Apply this rule to important events - 30th birthday parties, weddings, interviews and you'll rarely put a foot (or hair) wrong.