Go through the word mat with your child and read the words with them.
Help your child construct their first sentence as some children find it hard to get going.
Encourage them to say their sentences aloud before writing and using their phonics to help them spell.
Try and encourage your child to write the beginning up to Litttle Red Riding Hood meeting the wolf and the wolf going to grandma's house.
At this point you can suggest that you will carry on the writing but they have to give you the ideas . Encourage them to say sentences that a complete and make sense.