I agree with asking your friend how he went about getting his dogs registered. Also find out the age limit and wait as long as you can. Here I think you can wait till your pups are 6 months old. I think not registering at all would be way too risky. The council can only seize unregistered dogs.
And most importantly, make sure your pup doesn't cause any trouble of any kind, like escape from the yard or get into scuffles with other dogs, no matter how minor. Train, socialise and contain.