This is something both very simple and very useful for embroidery and patchwork.
This serves to Quilting (quilting or if you prefer), that is to say, to hold together the three layers that make up the quilt, the top (or top), fleece, and the lining. But it is also used to assemble parts or embroidery. The Japanese use it for the traditional sashiko example.

The secret to a fine point before: the regularity, that is to say, get to make points about equal length. Then the result is as if the finer points are small.

Now on to the practice. You remember sewing tests for your dolls? Yes .. super .. No? it does not matter!
It is simply to pass on here earlier in the fabric with your needle. This draws a dotted line with the thread.
Snapshots it gives this:

On the flip side of the book it gives this:

You can make several points at once! :

And hop!

And here it is:

Your turn!