I didn't know Michaels was dog friendly!
I like the idea of a nice walk too but you could also plan a little doggy birthday party. Have a little get together with other doggys, maybe even visit a doggie daycare if Layla likes that sort of thing and you can bring little birthday treats. And I know you home cook... can she have liver cake? Not the whole thing but it's really easy to make and I cut it into little bite size pieces and my girls love it!