The arrow that says 'Percent X' tells you which way the line goes for that soil component. So silt is Down-left, Sand is up-right, and Clay is Right-across. You can find the percentage of components at a point by going radially outward in the opposite directions i.e. find silt by going along the up-right line and seeing where it hits the axis.
You can find what type of soil you have from percentages by highlighting the lines for each percentage and then finding their intersection. Eventually (god help you if you can!) you will get comfortable with this behemoth and can figure it out by looking.
The arrow that says 'Percent X' tells you which way the line goes for that soil component. So silt is Down-left, Sand is up-right, and Clay is Right-across. You can find the percentage of components at a point by going radially outward in the opposite directions i.e. find silt by going along the up-right line and seeing where it hits the axis.
You can find what type of soil you have from percentages by highlighting the lines for each percentage and then finding their intersection. Eventually (god help you if you can!) you will get comfortable with this behemoth and can figure it out by looking.