Definitely start right away, and just be patient. We were amazed at how quickly Sandor picked up commands. He's 4 1/2 months and knows sit, wait, paw, down (inconsistently). He's also really good with sitting at crosswalks (we live in the city), and sitting when he see's other dogs approaching. He knows leave it (and does most of the time) and drop (and will allow you to open his mouth to get things). He will sit and wait for food and treats. He just had surgery so we are doing some free shaping with him, working into a spin command.