Apply to universites and colleges early in your senior year. There is no special application for students with disabilities.
September 1 - November 15 is the priority filing period. During this time, you might be accepted if you meet or exceed the minimum admissions requirements. After November 15, the office of admissions may increase admissions requirements and may no longer look at applicants who just meet the minimum.
For example, if you have a 19 on your ACT, you are in the 51 percentile of your class, meet all NIU high school course requirements and have a 2.77 GPA, it recommended that you apply before November 15. See Undergraduate Admission for Applicants with Disabilities.
If you are accepted to NIU and plan to attend:
If you are not accepted to NIU, you are strongly encouraged to enroll in a community college and transfer to NIU when you have your associate's degree or at least 24 hours of transferable credit.