Congrats on your new puppy and welcome back on G. Shepherd world! Got my pup when he was 7 1/2 weeks, started training right away. In 2 weeks he learnt all the basics: sit, come, look, drop it, let go. Learnt 'stay' when he was 4 months. Not pulling on the leash at around the same time. They're awfully clever, however for 2 - 4 months old, their attention is very short, never train for more than 15 minutes. After mental exercise they're usually worn out.