When our son was diagnosed with autism and behavior & intellectual challenges several years ago, one of the main points the doctor (who had 20+ years experience of working with children) made to us was that everything we wanted our son to truly and meaningfully understand should be wrapped in the context of “play”.
That advice has proved consistently true as our son has grown. Successful communication with a special needs child, preteen, teen, young adult, or adult who deals with autism and behavior & intellectual challenges is naturally and sincerely playful. It receives the most notable response.
I believe it makes the strongest connections and gains trust with the child you love and you want he or she to know that you love them.