If you want to correct lips that are irregular or asymmetric in shape and create the illusion of almost perfectly balanced lips, it would be easier to do before you apply color to the lips.
To balance the appearance of your lips while lining (before applying lipstick), first, divide the mouth into sections, and work on one section at a time until all the dotted lines are connected. And be aware that matte colors make lips look thinner while shimmery, glossy colors make your lips look fuller.
Make Thin Lips Look Bigger
Use a lip liner to outline your lips just outside their natural edge, making the outline slightly wider on the top and bottom. Then brush on a layer of lip color inside the outline. Spread on a layer of lip gloss on top of your lip color.
Make Full Lips Look Smaller
Apply foundation or concealer to the edges of your lips to blur the edge. Use a lip liner to outline your lips just inside the lip line, then brush on a layer of matte lip color.
Make Uneven Lips Look Balanced
Enlarge a thin top lip by outlining the upper lip just outside the edge using a lip liner, then outline the lower lip drawing the line on the on the natural edge. Brush on lip color inside the line, applying more color to the thinner half of the lip.
Make Shapeless Lips More Defined
Outline upper lip with a lip liner to emphasize the "v" in the middle before applying lipstick. Draw the line just outside the lip edge of the bottom lip to make it look fuller. Brush on dark, matte lip colors for even more definition.
Make Uneven Toned Lips Look Even Colored
Cover upper and lower lips with a little foundation. Outline lips with lip liner. Choose the lipstick color, then begin applying lipstick by brushing a darker shade onto the lighter lip and a lighter shade onto the darker lip.
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