You can start training from the minute you bring your puppy home

They are like little sponges at this age and anything a border collie can do, a yorkie can do!

Don't let anybody tell you toy dogs cannot be trained
Puppies will mouth everything (dogs ain't got hands like us

) so the trick is to do what another puppy in the nest would do if your puppy bit them oo hard - yelp ''OUCH!!!'' and turn your back on them, stop the game, walk away etc. It's amazing just how quickly they learn that nipping too hard (or ANY mouthing) leads to them being ignored

It doesn't happen instantly but PERSEVERE and be consistent every time and Puppy will soon get the message
As to general puppy/dog training - you cannot beat DR Ian Dunbar's fun methods

Make it a game with lots of rewards and Puppy will soon be on her way to being a well-trained member of your family.
Sirius Dog Training *bite inhibition is 5 minutes into video*