If we had, we would've taken Alpha to the Hobbes and Landes HOWL-o-ween Party for Dogs last October... and we would've slayed!
Well, there's no such thing as too-late-the-hero in this household. So we still went with making Alpha's costume, for future reference.
Now one tip when putting on a costume on your dog for the first time: If your dog --like ours-- is used to running around au naturel, there will be some grief dressing him or her up. So work with what's already there. Think of a costume that would take into consideration the color of your dog and the bare minimum of only wearing a leash with simple and light add-ons. Accessorizing is the best you can go with a first timer.
In Alpha's case, we went with How to Train Your Dragon's Night Fury. The costume is so easy and cheap to make.
And --it's done! Alpha was a little fussy when we started putting it on her. But later on, she got comfortable and totally forgot she even had wings!
So I guess it's a date next HOWL-o-ween?