How to make the embroidery of Petit Point?

The petit point embroidery is carried out using two of the six colored threads wound on the cardboard.
First, let's imagine a square made up of four points on the fabric. The line that we are going to draw must be oblique to the square, that is why we must always bring the thread to the part that will be the face of the embroidery and always from the lower left corner to the upper right corner of the imaginary square.
The next row should be done like the previous one, but in the opposite direction, although always keeping the line address. That is, now we will draw the same line slanted to the right, but from the upper right corner to the lower left corner.
In the event that you have to skip some squares in between, embroidery should start on the second row. From the second row we will go down to the first and then we will return to the second to continue going up to the upper rows (note the numbers in the image).

The difference of the petit point technique with respect to the cross stitch technique can only be seen in the back of the embroidery. Correct cross stitching avoids the appearance of oblique lines above the already embroidered parts, which is not ruled out in the petit point technique.