Validate who they are, their thoughts, experiences, what they can do, all things that represent their significance as a human. Emphasize you care about them and are there to help them. Your focus is on them and it is genuine. You might share about yourself; family, school, likes, dislikes, travel, languages.
Find out all you can about their reading trauma, when it may have occurred and how it has affected them. Identify something to ‘hook’ them into trying this out with you. Motivate them to read by giving them someone else to "help" like a sibling, parent, friend, teacher. Looking for beliefs about themselves they may have, their perceptions of their abilities in school, on tests, in math, in Language Arts, with peers, with adults, with their parents/guardians. What are their outside interests? You’re listening for school based trauma.
Let them know you are there to help and that no issue is too big. Discover any additional ways that you can determine to help this young person choose to read and be successful in this endeavor. Be sincerely grateful the young person is willing to trust you and that you have the opportunity to help them. "We have a plan and if you trust me, there’s a chance all of your classes are going to be easier for you."
Practice having them make connections and to think while they are reading, taking turns going back and forth until the young person is making their own connections easily. Consider the possibility the young person in front of you does not believe their thoughts are important. Ask if they have ever heard of connections. "Describe any thoughts you have about the words or sentences you are reading as you’re reading, after you’ve read them or before you even started reading." Ask them not to read out loud, to read in their heads. Reading fluency is tested in schools kindergarten to eighth grades, making connections has never been a goal in the reading process. Speed and trivia have been more important not making connections to what they are reading.
Hand them a stack of books to look through in order to find one that they know all of the words. The section "Books for Resistant Readers from 4th grade to High School" above is a great place to find books for older resistant readers. Attempting to help the person forgive books for being used as weapons, for being directly tethered to shame and self-doubt. Help this young person let go of their “illiterate” identity by allowing them to successfully read on their own with complete comprehension. Offer them a life-changing opportunity of agency. This is not the time to ‘sound words out’. This is the time to "give" them the words to help them move swiftly through their reading so they can make "connections" and become an independent reader.
It is not about the topic or about answering (trivial) questions about what they read, it’s about the importance of selecting reading material a young person can connect to. Make sure the young person can connect with the words. That they are making sense of what is in front of them and they can tell you about what they are reading with enough detail that you feel confident they are actually reading, thinking while they read, making predictions, providing evidence to prove themselves wrong, etc. Read one sentence at a time and repeat until they "get" it and can "connect" to it, if it's relevant to them.
Provide the time necessary for the young person to read with the knowledge that you’ll continue to be there for them and circle around to see how they did without any expectations. In a perfect world you would provide at least 20 minutes of silent real reading, either at school or parents can do this at home. Create purposeful, peaceful time for this young person to figure out how to make books come alive, like spark plugs in a car, they need that jolt. Allow for that jolt and trust that every child will experience that jolt.
Share any opportunity that can possibly help this young person as they traverse their reading journey. Let them know that your support is not the end. Explain how they can find reading material they can link to; their public library, other readers, best seller lists (New York Times, Powell's City of Books, NPR, Indie Bestsellers List, Goodreads, Amazon) and even author interviews on YouTube of authors they have enjoyed. Remind them that they are worth it and that reading will change their life if they allow for the magic to happen. Let them know they are like an octopus...reaching out all over the place to find the right book.