On that day, you will be encouraged to "Go for a long walk, visit friends, and Talk Like Jane Austen."
Helpful hints from the site, Talk Like Jane Austen Day, include:
"Always refer to your close family members as "my" mother, father, sister, brother even when speaking to one of them. For example, Elizabeth might speak to Jane saying, "My mother has been nervous the whole day." (Whereas we contemporary English speakers would most likely say "our" mother. (Note the use of "the whole day" rather than all day long or a more contemporary phrase).
No Contractions- "Don't you think this an agreeable morning for a walk?" Would be "Do not you think this an agreeable morning for a walk?"
More helpful hints will be published as the event day nears!