Highlighting is when you use a product either cream or powder based which contains light reflecting particles, when these particles catch the light they trick and create an illusion that makes things bigger.
The lips are one area of the face that women are always trying to make appear larger with the use of make-up. Whilst lining the lips is important to achieve a fuller lip many don’t realise how much a touch of shimmer/highlighter can drastically change the size of your lips. I find using a cream highlighter like N07 skin illuminator works best as it is easier to blend and tends not to sit on the skin, however if you would prefer a powder based product I recommend Bourgois Light Concentre de Lumiere.
To instantly open up your lips and makes them look twice as large apply the preferred highlighter to your cupid's bow and drag down along the center of your lips then carefully apply a small fine line of highlighter along the bottom of your lower lip, applying the highlighter in these areas will draw attention to the middle of your lip and create an illusion of bigger lips. Remember that whilst it may not look like a drastic difference in your bathroom, once outside it will be a lot more noticeable due to lighting, therefore don’t go crazy otherwise you will end up looking like you've been eating glitter.
Highlighting can also be used to create bigger eyes, simply take the same highlighter and dab it in the corner of your inner eye, this technique is a favorite of celebrity make-up artists.
This tip is easy to play around with and there are loads of ways to work with highlighter, I've only mentioned two but experiment and most importantly have fun.