You should try to cover up your own brow with powder, trim it or bleach to achieve better result, but I am lazy so my brows are showing.
Starting at the peak of your own brows (or around where it should be), draw a downwards sloping line using your brow pencil. Make sure it is long enough to balance well with your eyes.
Next, starting at a point slightly lower then the head of your brows, draw a line joining that point with the line you previously drew, taking care to make it a bit thicker near your nose.
See? The basic form of your Mana eyes are formed!
If you like you can go over you eyelines with liquid eyeliner; that way they will show up better in photos.
¡@