Use "you and I" when it is the subject of a verb. Use "you and me" when it is the object of a verb.
The first person pronoun "I" is used when it is the subject of a verb. When it is the object, "me" is used.
When using "you and I/me" the same rule applies: use "you and I" for a subject and "you and me" for an object.
I hope this helps.
More articles on "I" and "me" can be found here, and here, and here.