(Shame on me -- I posted this one day too late.)
He'd love it if you hauled out a copy of Oliver Twist or Great Expectations, and read a few chapters in his honor. Or at least check out some of his best quotes.
Read some of his letters. (Actually, he would have hated that -- he burned everything he could get his hands on.) Even better: check out the New York Public Library's digital overview of CD's letters, promptbooks and illustrations from his novels. (Thanks to the Berg Collection for this.)
Visit his home.
Or, more amazing: his personal bound collection of All the Year Round volumes, one of the periodicals edited by The Inimitable, including handwritten notes in the margins. These were discovered in 2015 completely by accident.
Happy Birthday, Charles Dickens. Glad you were on this earth for a time. These should be red geraniums...but roses will have to do.