You said you are going to call me tomorrow, right?
Genau.
Ok, so mich refers to me? Dich to you?
Richtig. The personal pronouns (mich, dich) are adapted to the person, the number and the case. That is, we decline them. The verbs often determine the case.
Oh, ok. So in this case we have anrufen. And this verb needs the... accusative?
Exactly!
Can you show me how those pronouns change for the other persons?
I can not only show you that, but also how they would change for dative.