I agree--search on youtube. The clicker works really fast, you sit the dog down, click and immediately give him a treat. Do this about 20 times so he knows click=treat. Take him out to the pile of logs and let him mess around with them. If he puts his mouth on one, click and treat. Don't tell him to do anything just identify the behavior you want by clicking and treating when he puts his mouth on it. If he picks one up, click and treat big time with several treats. Once he catches on that you want him to pick up the log, call him to the other side of the yard and click and treat. Eventually you can give a command like 'timber' or 'carry' or whatever you want and he can do it on command. Clickers identify the desired behavior first, then reinforce the performance of the behavior after a command. But start with sit or down or something easy. That's my Reader's Digest version of how to teach him to move a log.