Don't apply lipstick without sharpening the edges. This will make the lipstick bleed into the natural creases of the skin around your mouth. Instead: Line the outside of your lips in concealer for a sharp look that will make your lips pop.
Or, make use of your concealer and lip liner to make your lips look fuller. Use a lip liner one shade deeper than your natural color to line just outside of your lips. Fill the center with concealer, then apply lipstick on top, then lip gloss.