These coloring pages are perfect for teaching articulation!
Print them out and have them on hand.
Teach your student, that to make an SH sound, our teeth are closed, our lips are forward (or "kissy fishy"), and air flows out like a mist. Use gestures and facial movements to exaggerate the lip position and airflow.
Compare the easy to see mouths so kids can learn the difference between sounds, like "sh" and /s/.
As I hold up both the "sh" and the /s/ pages, I say something like, "See how for the S, our lips are shaped like a smile, and the air comes out from the center or our two front teeth, but for the SH sound, our lips are "kissy fishy" like this (and show them with my mouth) and our air flows softly like a misty fog." I make sure they understand the difference between the two, focusing on the teeth, lips, tongue and airflow.
You can also compare it with the TH, teaching how for the TH, our lips are shaped like a smile and our tongue is sticking out, but for the SH, our lips are pursed and out tongue isn't showing.
Then, I hand out the coloring page and ask them to carefully color all the parts: lips, tongue, teeth and air.
You can have them say the sound as they color.
In a group session, I have the kids color in between turns.
Once the images are colored, I save them for further sessions so that I can point to specific parts on their drawing to remind them which part of their mouth needs to be adjusted.
Full page, easy to see and color.