First, keep in mind that dyslexia does not hurt intelligence – in fact, since many dyslexics are visual thinkers, it may even enhance speed and creativity of thought.
Second, understand that a dyslexic student may have experienced a lot of failure and frustration, and a lot of undeserved negative labels such as “lazy” or “uncooperative.” They may have internalized some of this.
Third, be aware that they may have additional specific issues caused by perceptual flexibility. For example, they may have trouble writing legibly, or their time sense may distort if they get bored or confused and make them act like they have ADD. In fact, any dyslexia-related problem will probably get worse with boredom, confusion, or other negative emotion.
So, approach the child with the full expectation that they are capable of learning anything they’re interested in. Show them that you want to engage with their creative curious mind. Talk to them and listen to them. If they’re old enough to understand it, maybe give them a copy of the book The Gift of Dyslexia (available on CD) which may help them understand that dyslexia is a very specific problem that has nothing to do with their intelligence or capability.
Then, start teaching and/or tutoring for success: Find a way to engage their interest, whether it’s through art, story, facts they want to accumulate, or however else they want to engage with the material. Remember that their point of view is what will control how well they learn. If they are not interested or motivated, it’s your problem, not theirs.
Dyslexic reading disability (and other dyslexia-related problems) are correctable, but before or until that happens, just learn what triggers their dyslexia and avoid it. This may require avoiding written text, and that is a significant limitation. Treat it the same as teaching a blind or deaf student – they have a fully competent brain, and simply don’t have one learning modality available