At the bottom, you have the choice to change the colors of the column. First, do just the leftmost colors for each row. Change the color, click the up arrow. See if the combination lights up green on any row at the right. Of course, you have to change the color for the right too, but that doesn’t matter now. Once you find out which color of the left column lights up green on each row on the right, note down the sequence. For example, first row: yellow, second row: red: third: green, etc. Now, work with the right sequence of the colors on the left column. Eventually, you will find out the exact color of each row (i.e. first row: yellow/red, second row: red/yellow, and there you go). It will just be a matter to arrange them in the right order by pressing just the up/down arrows.