Read the short story containing 12 words with the ‘tch’ sound.
Images are included for the child to follow along.
Try to embed the story in the child’s memory by reading it several times.
Get the child to retell it, with the images visible.
Gradually cover up an image at a time and see if the child can keep the words in mind while telling the story.
Hopefully, overtime, the child will retain the entire sound story or have inspiration to create their own!