You can alter the appearance of your lips depending on how you apply your lip liner and the colour of lipstick you use!
If you have small lips, don't be afraid to draw just over the natural line to give the illusion of fuller lips. A bright colour will further emphasise your lips.
To downplay fuller lips draw slightly inside the lips and select a darker shade of lipstick.
To aid uneven lips, use a lip pencil to correct a natural line by following contours and creating the shape you want. Blend the line to avoid a hard line.
More tips:
Lipstick | Lip Liner | Full / Thin Lips