In the almost decade that I've painted faces, no client has asked me to make his or her lips look smaller; and while I tend to highlight my eyes instead of lips, I know lips are the main facial feature many focus on. Since there are about 72 million or so videos/tutorials on how create a larger lip line, I'm specifically showing how I fake fuller lips that a) look natural and b) work even if you don't have perfect lips. If you're a visual learner like me, check out this video (yes, I broke down and started a YouTube channel).
1 - Prep Lips
Apply a little lip balm, then blot with a tissue so your lips are hydrated but not slick. If they're really dry and flaky, mix a couple drops of olive or coconut oil with 1/2 teaspoon of brown sugar, then gently exfoliate your lips with this paste. Wipe it off using a damp wash cloth, then apply the lip balm and blot.
2 - Apply Concealer
Using a small dot of concealer, apply to lips and the skin around them.
3 - Fill In
Using a flesh-toned lip liner, fill in your lips making sure to draw just outside the natural lip line. If you have uneven lips like I do, this would be the time to even them out.
4 - Lipstick
Apply a matte lipstick with a brush over the entire area where you applied lip liner.
5 - Contour
To start adding dimension, line your lips just on the created lip line with a pencil that's slightly darker than the lip color. Blend gently with the lip brush.
6 - Highlight
In just the center of the lips, apply a matte lipstick lighter than your original lip color and tap with your finger to blend.
7 - Brighten
Unless you like the matte look, top your highlight with a small amount of gloss in a similar color.