Variety is great, but some fashion rules exist for a reason. They help us throw together a perfect outfit in a pinch and provide a foundation on which we can incorporate patterns an accessories to show off our unique flair.

One set of guidelines most women don’t know about involve necklaces and necklines. Should you pair fine gold jewelry with a sweetheart evening gown? What about a choker with a Peter Pan collar? Stress no more; here’s how to find the perfect necklace for your neckline:

First: Consider length

“The higher the neckline, the longer the necklace.”

A good rule of thumb: The higher the neckline, the longer the necklace and vice versa. That said, shorter necklaces are generally more versatile than their 20-inch counterparts. Still, you wouldn’t well a collar necklace with a turtleneck.

Sound confusing? Here’s a brief rundown of lengths versus necklines:

  • 14 inches/Collar: Like a regular collar, these rest at the middle of your neck. Collar necklaces look great with open-neck clothes that show off your shoulders or bust. Think strapless, sweetheart or boat-neck outfits.
  • 16 inches/Choker: The staple of ’90s punk teens is back in style. Unlike collars, chokers are supposed to sit at the base of the throat. They work well with most necklines.
  • 18 inches/Princess: If your outfit looks a little too plain, try a princess length necklace. These sit on the collarbone and are great for jazzing up conservative outfits without being too provocative.
  • 20 to 24 inches/Matinee: These necklaces fall right between the collarbone and the bust. They’re very versatile and come in a wide variety of styles. Matinee necklaces look great with a variety of necklines, but they aren’t always the best option for low-cut tops.
  • 24 to 32 inches/Opera: The name should make you think formal wear, as opera-length necklaces are perfect for an elegant evening. They fall right on or slightly below the bust, but you can wrap them around twice for a more unique look. Most multistrand necklaces will be either opera or rope length.
  • 32+ inches/Rope: Anything longer than 32 inches is considered rope length. This are for your most upscale outfits – think dress suits for women and eveningwear.

Second: Look at size

Should you wear thin gold jewelry with a paisley top? Probably not, unless you want the necklace to disappear in the fabric. Similarly, a necklace that has too many embellishments will clash with a lace and other intricate choice. This means you should pair eye-catching jewelry with subtle outfits and vice versa. Solid colors are great for brilliant pendants, while chunky gemstones look nice with small, delicate flower patterns.

All fashion rules can be broken, but they’re also great to rely on in times of need. Keep these necklace guides in mind, and you’re sure to create a stunning outfit every time.