I have other players read out information from my dyslexic player's character sheets when necessary, and I use non-verbal visual aids whenever possible. I generally give out copies of any important visual aids, such as maps, riddles, or red herrings, to be contained in a player binder that can be referenced whenever anyone feels the need to review. The players are all responsible for doing their part to keep the game running smoothly, such as tracking experience and treasure. Generally, my dyslexic player moves minis around a map while my autistic player focuses more on tactics and keeping up general party paranoia.
I plan to start incorporating auditory clues to signal different segments of the game, such as the start of a session, breaks, and ending the session. I will also make up notes in the OpenDyslexic font and see if that helps make things easier.
The major problems I run into are my dyslexic player has trouble keeping track of details regarding her character and the other characters, since looking at character sheets tends to bother her, and that hurts her ability to really get into character. My autistic player often wanders off into "what if" territory, even during combat, such as "what if this unarmed kobold here were actually the leader of a second band of kobolds, and is going to come back and kill us later if we let him live?" That's not a problem itself, of course, but the other players get annoyed with the frequent divergences from what is going on in the game, and momentum stalls while the game drags on.
I would like a better way to help her keep track of mechanical minutiae, and a better way to help keep him a bit more focused during the games.
Best Answer
To help eliminate your dyslexic player's issues with reading a character sheet, you might try making a "homebrew" stripped-down character sheet with more imagery and iconography than words. For instance, a humanoid shape with notations of the weapons the character is carrying near the hand that is carrying it, and a big number on the chest to denote AC or health. This would help the player to make a better association between the pure data a character sheet represents and the in-game information it corresponds to.
In addition (as Tom Bonner has noted), giving descriptive and contextual names to areas and items can help eliminate the barrier that written word presents. Calling a cave town "Dark Rock Village" or giving the town butcher the last name "Meet" might help.
As far as the issues your autistic player has with focus and concentration, it may be helpful to review tactics that teachers of autistic students use in classes, such as those given here. Structure your gaming sessions well, so they can be used to the pattern. Utilizing multimedia may help improve focus; play the same (quiet!) music every time the party enters a town, for instance, or when they go in to battle. Make an NPC's clues to the party into a song. Have props on hand for someone who can better visualize things by touch than visually.
Incidentally, I don't think that any of these things would impede your non-dyslexic or non-Autistic players. It seems to me that these are all additions that could improve any GM's game, whether they have dyslexia or autism or neither condition.