Okay, he's not a GSP, but I'm afraid my two GSPs are going to pick up bad habits, so help!  I'm  petsitting a friend's young Aussie and he's driving me nuts climbing in my lap (and mouthing my arm).  Shoving him off with "NO!" doesn't work.  I have a crate for him; should I try immediately putting him in his crate when he starts to climb up, and then letting him out in 10 minutes?  How about tethering him?  Squirting him?  I'm looking for a quick fix although I'm sure my friend would be appreciative of any improvement!  I don't have a lot of good discipline skills because Chelsea and Jasper, bless their hearts, are really, really good dogs.  (Except when she goes nuts barking at a cat and I have to throw a rake at her.)

I have been putting him firmly in the "down" submissive position which he understands real well. He goes submissively limp. . .and then hops right up when I release him and back to climbing up.  I don't want to get up and leave the room because this happens in the den while I'm watching TV and why should I be the one punished?     I may try turning my back. and ignoring him . .then its the squirt bottle.   

You could put a 'tab' leash on him and stomp on it when you've pushed the dog down onto the floor. Or put a blanket or bed on the floor and keep dragging the dog back to it the nanosecond he gets off until he realizes getting off it is no fun and doesn't get him very far.

HOWEVER....  IMO if you're going to have any success, you need to make BOTH halves of the message very consistant and clear: on you BAD, off you GOOD. That means all attention/treats/maybe even meals from now on needs to be while the dog is behaving/lying down/on his rug. If that payoff for good behavior isn't sufficient, he'll probably continue to decide that the threat of punishment is worth the additional attention it gains him.

I would also consider a dog like this a prime candidate for an extended, or even perminant, 'nothing in life is free program'. I'm no expert but I rarely see rude and bossy behavior like this in a vaccum.... such dogs are often rude and bossy about darn near everything. Example: if you give a command the dog knows, particularly one that puts the dog in a submissive posture like 'down', does the dog bark at your face before he complies? Or just refuse outright? Does he shove his way through doors, especially before you go through? Does he swat a paw or claw at you until you pet/feed/hand over a toy? Owners will often excuse this type of thing, but IMO it's all the doglish equivalent of giving the human the middle finger and needs to be dealt with head-on.

The good news is that my most bratly 'nothing in life is free' dog is mostly very well behaved these days- with periodic tuneup sessions.