"Tomorrow you go."
Translation:Morgen gehst du.
Well, was that in the imperative section? It could also be a normal indicative sentence. However, if used as a an imperative I'd expect an exclamation mark at the end: Morgen gehst du! In speech, raise your voice!
You are right, it's not a standard imperative. That would be Geh morgen!. Sometimes Germans use the indicative phrase as an imperative. It emphasizes the person that is explicitly mentioned (the addressee is rarely mentioned explicitly in a normal imperative phrase). You must go... but she can stay! One could even use the indicative phrase Du gehst morgen and transform this into imperative Du gehst morgen!. However - exactly like in your example - it's more likely to put the pronoun at the end. Has a better ring to it....
All in all. it's almost like in English: Do it! No, you do it!