I am going to disagree w/ you all on this. Take your pup out early. Just do it bu yourself and make it kinda low.IE. jumpshooting ducks or put and take phesants.. He'll love it, you'll like it too. Still work on the basics but give him a little time to expirience a few birds.
I took my chessie out for the first time when he was 7 mos to a put and take phesant place and killed 10 birds over him. It took him a while to get the hang of finding the birds but he had it pretty much ironed out by #5. I took him dove hunting the nextweek, and he got to retrieve a few more.. By the time he was 9 mos we were killing 20+ ducks over him a day out on the bay. W/ no major issues, except he wasn't real steady yet. Were getting ready to start our second season duck together this year and I can't wait. Espically after watching him wack crippled early geese this year. Bottom line, Training is great, but it is nothing w/out real world expirience.
Also, NEVER NEVER NEVER, play fetch w/ anything but a bumper or you'll create a fetching monster who raids neighbors yards insearch of fetch toys.