From the historical process of calligraphy evolution, first teach him to "draw characters", such as seal script (big seal script) or official script. You can write some words such as "life", "bright moon", "happiness", "beauty", "dance" and "aboveboard", which are both easy to write and meaningful, and foreigners are also interested.
The characters of horizontal and vertical strokes are the best and easier to master.
Try again and teach some regular script. Running script is really difficult for them to learn. Try to teach some "childish bodies"!
Good luck with your teaching!