Just draw letters on a big board and let the patient point at them. When it’s a possible solution, it is surprisingly efficient as you can guess orally and he “thumbs up” so he doesn’t have to spell everything out, and after a few tries you can tell stories. You can add bonus pictograms for ideas that repeat.
Thoughts to a fiend I cared for, a few days per week during his last months. After one night playing guitar, he never woke up, and I realized he went to sleep while we were singing him his own songs. What an enemy he was during life, he would have killed me if he knew my political opinions, but once he became weak and harmless and alone, no-one deserves to go alone. If only such people didn’t fight so much against the white christian male ceo archetype during their life… I hate life.