Ask broad, open-ended, slightly vague probing questions to get students to open up and engage with you (including questions not about their writing).

Don’t be phased by momentary silences while the student thinks, it’s OK to wait. 

Use encouraging language to get them to make changes.

Go through the topic slowly, paragraph by paragraph, idea by idea.

For quiet students or distracted students, use the topic to engage with them to bring them back to writing.

As they talk about their ideas for the paper, take some notes for them.