The biggest foundation mistake women make - sorted.

Carla GS applying Too Faced Born This Way Foundation (Light Beige) with her fingers. Source: Supplied.

There’s one thing that separates the maestros from the amateurs when it comes to makeup application, and it’s the way you apply your foundation.

Few things are more masterful than an even, seamless veil of foundation over the face. Conversely, a mask-like application of foundation, which results in an obvious line where the foundation ends on your face and the bare skin of your jaw begins, is just begging for a little makeup advice.

Why does it happen? And how does it suddenly appear when you swear it was blended when you left the house?

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According to celebrity makeup artist and cosmetics entrepreneur Liz Jones, this common foundation problem is known as a “high tide” mark and there are three genius ways you can avoid it.

“The most obvious reason for the ‘high tide’ mark is not working the foundation into the skin enough and spreading it out below the jawline,” advises Liz. (Post continues after gallery.)

3 tricks for avoiding that foundation line.

1. Select the right shade for your skin.

Choosing the right shade of foundation is key. “If you haven’t matched your foundation to your skin tone, blending is going to be hard work,” Liz warns.

So, how do we go about selecting the right foundation? Last time I tried it, my daughter was screaming and trying to grab all of the Maybelline testers for herself, so I was shamed into buy the wrong shade. Surely, there has to be a better way.

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Liz’s big tip is to always take a step out into daylight when sampling a foundation, to see how the shade looks on your skin in the natural light. “Whatever matches in daylight will match under any other conditions,” was Liz’s genius advice. This is because, she says, “instore lighting can be too green or blue because it’s artificial lighting”.

This video by makeup artist Lisa Eldridge also has fantastic tips on choosing the right colour of foundation. (Post continues after video.)

2. You need to start applying foundation to an area other than your face.

Well, now that we have blending and colour-matching under control, we should be on top of this foundation thing, right? Wait – there’s one more foundation trick to keep in mind, and this one’s a doozy.

“You always need to put a dab of foundation on your neck… roughly about the centre of your neck halfway down,” Liz informed me. This sounds crazy, but there’s a really clever reason behind this.

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“We get this patch of lighter skin under our chin, because shadow from the chin stops natural colouring from daylight,” explained Liz.

3. Blend, blend, blend.

Your best tool for blending your foundation? Your fingers! Liz’s chosen tools for blending foundation are fingers for liquid foundation, and for powder foundation, a brush that is soft, malleable and fine-bristled.

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Now that I know the secrets to applying foundation, there’s never any excuse for me to have the dreaded “line” on my face. I don’t usually believe in beauty rules, but avoiding the “line” is my top makeup priority. I’m saying goodbye to tide marks, and hello to smooth seas ahead.

What are your best foundation tips?