Before the radio, how did the orders get issued during large battles?

The dispatch messenger riding back and forth to a sub commander I guess was one common thing, but was there other means?

There had to be plenty of misunderstandings given that the situation had changed between the order was issued and it got to the sub commander. So did the local commander usually have a lot of freedom to alter commands or was the norm that it was carried out nevertheless?

Also, if I might convolut the question even more; How did the local section commanders get it through to the men fighting?

I'm here thinking of battles of thousands of soldiers, and fully understand that this is something that could vary immensly between ages and generals, but examples would be interesting to hear about. :)