This is the easiest thing you can do to avoid nasty soot marks on your candle jars

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The INSIDER Summary:

• Not everyone knows that there is a right and wrong way to burn a candle.
• The first step is to always trim the wick.
• Trimmed wicks make for a cleaner burn with less smoky residue.

Ever buy a brand new candle only to watch its glass jar turn black and smoky? There's a way to prevent those unsightly smoke stains, and it's incredibly simple: Always trim the wick.

This was the most important thing I told customers when I worked for Yankee Candle, and I still abide by the rule in my own home.

Start by trimming the wick to 1/4-1/8 of an inch in length, every time you burn.

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Trim the wick like the candle you see on the left.

You can use a plain old pair of scissors to do this, but once the candle burns down, it'll get harder to reach the blades far enough into the jar - that's why I like to use nail clippers instead.

But if you're a serious candle fanatic, you might want to invest in a wick trimmer. Think of them like a modified pair of scissors built specifically for this purpose. You can find a trimmer online for around $10.

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Here's what a wick trimmer looks like.

Trimmed wicks make for a clean burn.

Check out the difference between these two flames. Trimmed wicks make the flame look clean and bright. Untrimmed wicks are a lot more likely to take on a weird mushroom-esque shape (see below) that dulls and obscures the flame.

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Trimming makes a difference.

And you'll avoid smoky candle jars, too.

Untrimmed wicks are a major contributor to that unsightly black residue. Short wicks make for a controlled flame and less smoke. Need proof? Here's a candle we burned for several days with an untrimmed wick:

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Don't want your candle to look like this? Trim the wick!

But for this candle, we trimmed the wick before every burn:

Caroline Praderio/INSIDER

Of course, wick trimming is only part of proper candle burning technique - but it's a crucial (and easy!) way to get more from every candle you buy.