PUPDATE: Using a Dog to Herd Goats

Our Australian Shepherd, Levi, is a year and a half old now.
He is coming into his own, and a huge help on the ranch. With our kids all grown, it is just the two of us, we just don't have enough hands between us, and we aren't as agile as we used to be - so we decided to get a puppy. He has had no formal training - just informal experience - but his instincts are spot on - and he is smart. The LGDs know he is in there to work - and what his work is - so they don't interfere.
We were told it is hard to get dogs that are good on goats, because goats will challenge a dog and don't flock like sheep. We must have gotten lucky.
Do we use the "right" commands? We don't. We use commands that work for us.
He made short work of penning on several occasions yesterday as we brought the goats into the catch pens and moved into sorting pens. We are so grateful for him!