Dress as your partner

I just put on his clothes and stuck a "Hello my name is" sticker on my chest that announced that I was "Carl on another day."

If you have access to a lab coat, go as a scientist. That was my standby for many years.

A Stepford wife... you might have the costume bits and bobs in your closet already. I added contact lenses that blacked out my irises for a subtle dehumanised look.