Huntress, we had that issue with a bc at 4-h. It was a long road. And lots of work for the owners.
We taught her to herd on command. And to stop on command. It is a lot like the leave it game. No reward until the attention is COMPLETELY off of the herded item. Meaning you need much more focus on you instead of the herding. So I suppose it is hard seeming when the herd item is feet. We used a giant rubber ball at first. Had her chase it and tell her to get it. But kept a line on. So we could correct from a distance when she was told to leave it. Then the leave it part should be transferred to any item herded.
Good luck!
We taught her to herd on command. And to stop on command. It is a lot like the leave it game. No reward until the attention is COMPLETELY off of the herded item. Meaning you need much more focus on you instead of the herding. So I suppose it is hard seeming when the herd item is feet. We used a giant rubber ball at first. Had her chase it and tell her to get it. But kept a line on. So we could correct from a distance when she was told to leave it. Then the leave it part should be transferred to any item herded.
Good luck!