Creating an accessible and inclusive event should be part of planning from the beginning. Some simple accomodations and forethought can make an event inclusive for a diverse audience.

Use the invitation/RSVP step as a time to note that accomodations are available: simply ask guests to include any special accomodation requests with their RSVP. This will give you plenty of time to plan your event with all of your guests' needs in mind. 

As part of your parking plan, be sure to identify the closest handicap spaces and alert your guests to their location. 

Check out this great handout on planning programs and events with accessibility in mind, produced by UT's disABILITY Advocate Program.  Also visit Services for Students with Disabilities for more resources on campus and classroom accessibility.