The concealers/correctors come in a two layer compact, with orange and green in the top, lavender and green below. Initially I thought the top layer's orange would disguise dark circles, but that required an ordinary concealer to hide the orange. One day I tried the lavender alone, with nothing on top, finding it easily removed the dark circle.
It is quite dry, but the solution works immediately - a drop or two of jojoba, rose hip, argan or whatever, oil, repeated when needed. It then very easy to use and works really well. The lavender worked for me, so experiment until you find the colour or blend that is right for you.
Blend it for under eye circles, imperfections, spots, anything that needs a concealer.