The illustration shows the typical string layout of traditional koras, in this case in G-major.
The scale begins on the left with the lowest note G2(1), followed by D3(2), E3(3) and F#3(4);
A2, B2 and C3 are not used, there is a skip of a fifth between string 1 and 2.
The next note in the scale is G3(5) on the right at which point notes begin to alternate between right and left, so A3(6) follows on the left, B3(7) on the right and so on, down to G5(19) on the right.
A5(20) and B5(21) finish off the scale on the right.