Translation
This play is done like this. Against one who makes a middle blow against my middle on the left side, I immediately go with cover to the narrow and throw my sword at the neck of the player as shown here. I can throw him to the ground without fail.
Interpretation
Against a horizontal mezana cut to your left side, respond with the master play using posta frontale. Turn slightly to your left and step through with your left foot, pushing your opponents sword before you.
Bring your right foot up and as you do so, grab your sword in the middle of the blade with your left hand. Continue the movement of your right foot, swinging it behind your opponent to land between their feet. Reach over your opponents head with your left hand as you do so. This is the picture point shown.
Make sure that your shoulder girdle, your arms, and the sword form a circle. As you sink your weight onto your right foot, roll that circle into a vertical plane and then down. Although it appears in the picture as if the crossguard is going to catch under your opponents chin, ideally you want your right hand to slide past their neck, leaving their head cradled in the hollow of your shoulder.
Your left hand comes to rest by your left shoulder, and your right hand just inside your right knee. Your opponent will be thrown on their back at your feet.
With some variation, you can see this same basic throw being used in different contexts in the following plays.