Define within your syllabus and discuss in class the essential criteria of the course. Essential criteria are tasks, knowledge, skills, and abilities needed for students to be able to understand and learn the course material. The DOT list tasks, knowledge, skills, and abilities required for specific jobs. It is imperative that essential criteria can be demonstrated to be essential. It is not enough to simply state what an essential criterion is.
Accommodations are a problem solving process.
Hence, communication between the professor and student is imperative. Discuss options with students, including ideas for accommodations that you think are appropriate. Your presentation and attitude are imperative to successful implementation of accommodations. If possible, provide study guides for quizzes and exams. For example, changing a multiple choice exam into an essay exam.