use it with matching lip liner. That way you will prevent

lipstick from spreading over the edges of your lips.

If you are using transparent lip gloss, it’s not necessary

to use lip liner, although you could use it as long as you use

some natural shade and color.

For toned lip gloss you could use matching lip liner,

but try to make gradient effect from the edge of your

lips towards the center.

That way you will soften the sharp line made by lip liner.