Streamline words with path tools

At the request of a large number of friends, I wrote this tutorial. The original tutorial area was similar to this one, but some people said they didn't quite understand it. That one was previously reprinted by me, now I want to write a graph by myself. I hope you can understand it.
When you are reading the tutorial, I hope you can follow it. In my example, you can also follow the melody, step by step. After the figure is ready, after understanding how to do this, go to another exercise :)

First look at the effect:

Start: