There is no magic secret for the discussion part. But yeah you can follow some steps and process for the discussion part. Here I’m giving you a brief about discussion.
If you are starting first be confident and readout your story.
Listen others story and relate with yourself.
When you are giving logic also relate others match cases with your story
Relating with others story would make your logic more strong.
Follow PPDT guidelines to build logic, consult experienced mentors.