There are Apps for that.
Pretty much every modern smartphone can be used as a angle finder.

I aligned my Dart with my iPhone and an app called "iAlign", and later used one called "CamberMeas" which has become my favorite.
In the latter app you can enter your car's steeringratio and it will let you turn the steeringwheel one turn left and right.


The most tricky part is being able to mount the phone securely/square and easy removable while being able to get repeatable results when checking the left and right wheels.