1. Trim the wick before every burn!

Each time you want to burn your candle, start by trimming the wick to between 3 to 5 mm long. You can use scissors, or a wick trimmer, a wick trimmer like this from Amazon. This is a very important step to ensure even burning.

Trimmed wicks will give you a cleaner, brighter burn. Untrimmed wicks are a lot more likely to take on a weird mushroom-esque shape that dulls and obscures the flame. 

Excessively long wicks are a top cause of those nasty smoky stains that end up on your glass jar candles. Trimming the wick keeps the flame in control and prevents those marks from forming in the first place.

2. Let the wax melt all the way across. 

Once your candle is lit, don’t blow it out until the top layer of wax has melted all the way across. This might take several hours — so don’t set out to burn a candle at all unless you’ve got time to kill. 

Whenever you fail to achieve full melt, you’re contributing to a process called tunnelling. The wick starts to sink lower and lower, like a tunnel is forming right through the center of the candle. 

Eventually, the tunnel will grow so deep that it’ll be tough to light the wick at all. More importantly, all that unmelted wax on the sides represents hours of lovely fragrance and burn time you bought but won’t ever get to utilize. 

It takes patience, but if you melt the wax all the way across every time you burn, the surface of the candle will stay  flat and the sides of the jar will stay clean, all the way down until the candle is spent.

3. Only burn your candle for a maximum of 4 hours at a time.

If you burn your candle for more than 4 hours at a time, carbon will collect on the wick, and your wick will begin to “mushroom.” This can cause the wick to become unstable, the flame to get too large, your candle to smoke, and soot to be released into the air and around your candle container. Always keep an eye on the candle for mushrooming and if this occurs just get rid of it by cutting it out.

4. Keep the flame away from moving air. 

Do your best to keep your burning candle away from fans, air conditioners, open windows, or heavily trafficked areas where people walk back and forth a lot. Moving air can disturb the flame, leading to even more unsightly black marks on the glass.

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