And for the daytime engagement, she dressed down a suit with the ultimate cool girl ... Letizia brightened her monochrome gray look with a subtle burgundy smoky eye and a natural pink lip.

Often pictured in a well-tailored trouser suit and carefully ... "If you're new to monochrome dressing, begin with neutral ...

Considering it's a two-piece matching set, a suit alone gets you halfway to mastering monochrome. But when you add a matching shirt or coat, you're putting the cherry on top of the sartorial sundae.