When I was at school, we were taught to strip away the you and and see if the personal pronoun sounded correct on its own.
Technically, I is nominative and me is objective. If you bung you and in front of it, you must still use I when it is the subject and me when it is the object.
Here are some examples:
You and I have been living in Bathurst for over seven years now.But I fear that you and I is going to completely replace you and me.
It's very important to you and me.
Public speakers, including preachers, use it wrongly all the time. The only Christian minister I hear using it correctly is Peter O'Brien, research professor at Moore College.