I started by putting food out near them and slowly building trust. I would look at them and talk to them.
By the time I read you aren't supposed to look right at them, I already had success doing the opposite.
A big thing is to never try to be sneaky. Move slowly, but if they think you are trying to fool them they won't trust you.
If you look at my history, there are lots of photos of my corvid pals. :)
Good luck to your wife!