Necessary materials: watermelon knife and watermelon

1. As shown in the figure, select a quarter of the watermelon, cut the first knife, and be sure to cut it from the top to the bottom;

2. Cut the second knife on the other side of the watermelon belly button, that is, 3/4. In order to keep the watermelon beautiful, the second knife should be kept parallel to the first knife as far as possible and cut vertically down along the blue line;

3. The three knives should be perpendicular to the incision of the red line and the blue line as far as possible. As shown in the figure, the green line should be cut vertically downwards, and be sure to be vertical when cutting;

4. In the same way, cut the fourth knife parallel to the green line, and you can see that it is now a "well" shape;

5. Finally, cut a watermelon into 4 knives and 9 watermelons, and eat up 9 watermelons. Because the position of 9 is a cube, you get 1 skins.