We have one pup, how to choose the 2nd?

We are adding a new puppy to our family and need some advice on how to choose btw 2 pups and what to do when we get home? We have a one year old male mini aussie and are deciding btw 2 female mini aussies. One followed our aussie around and was ppl friendly. The second was very ppl oriented, but did not have as much interest in our dog , still checking him out and playing with his leash though. The breeder was leaning towards the 2nd female before we visited. This is the same breeder for our dog. Our dog didn't show interest in one over the other.

Once we get our new pup home, we're not sure what to do in terms to socializing, bonding with, training and adjusting the new puppy with our current dog.
Thanks in advance!