Teaching dyslexic child to read
The best advice I can give here is to use something to block out the page where you aren't reading. For example, have half of the page covered by a sheet of paper, or even move a sheet of paper down line by line as the child reads. This helps them to focus, sometimes their eyes see all the letters and it becomes a big, ugly jumble in their head.
Also, it seems that books with less print per page and larger letters make it easier for kiddos who are learning to read. Their eyes process the letters better because there is less distraction in their sight.
Now, there's no good evidence for this one, it's just something I noticed with Mini when she was learning to read. She relied very heavily on phonics because that's how her brain was wired. She had the worst time with words that did not make sense to her phonetic understanding (ph and f for example) and would get highly frustrated. When she would write words she was a heavily phonetic speller, she spelled how she heard it in her head while sounding it out, even if she had seem the word 100 times before.
Unfortunately a lot of schools teach only phonetics for reading and spelling starting out. And it makes sense, most children learn this way and then can adapt to sight words as they get older. With my daughter she needed to have sight words mixed in with phonetic spelling and for those sight words to challenge her away from sounding things out to spell/read them. Our language is full of words that can be spelled different ways, or with extra letters or letter combinations that phonetically make no sense.
It took a very long time to break my daughter out of this, and even to this day she struggles a bit. She can read anything you put n front of her but spelling is a struggle.