It wasn't anything like groups of 10 running around. Here's an example of an offensive by the Soviet 69th Army. The diagram only breaks it down to the front of each division, but each division would have objectives set for all of its regiments along that front, each regiment would have objectives set for its battalions, and so on. Once you get down to the squad level (the 10 guys running around), they will have a series of very specific objectives on a very narrow front, like knocking out machinegun nests, taking a certain trench, etc. These actions would be synchronized with aircraft with schedules like these. Infantry commanders would meet with their supporting artillery and tank commanders personally for reconnaissance and synchronization before the attack, so the support would have at least a rough idea of where and when their infantry will be, even if direct contact is lost.