I was hoping you guys could give me some tips on how to train my BF's family to train their boisterous and basically untrained boxer. I've only ever trained my own dogs, so a lot of times I guess I go kind of on instinct because when it comes to telling someone else what to do I've realized I'm pretty terrible! 
Problems:
1) Jumping on people/climbing on them
BF's family likes to push the dog off and yell at him. Dog thinks pushing is fun, and doesn't understand why he's being yelled at. He's too big and strong for the "ignore it and praise calm behavior" method to work. Should they progress to a squirt gun (which he finds mildly aversive), crate him, or put him in another room? Or something else?
2) Counter & trash surfing like crazy
Um... don't leave things on the counter? That's about all I got. Anything else they could try?
3) "Go lie down"
They basically want a "go away and stop being annoying" command, yet they for unknown reasons think the dog should understand them when they yell "Go lie DOWN!" without having previously trained this command. (?) They think because he occasionally goes away and lies down when they yell at him he understands what they want, and they don't understand why he doesn't listen to them all the time, so they just increase the volume of the request until he does, and which point they ignore him. lol.
What I told them yesterday is that they need to be consistent with their followup (not just saying it over and over, actually making sure he does what they want when they ask him) and they need to reward him for doing things right. Part of the trouble here is he gets SUPER excited with any reward/praise/attention, so they're having a hard time teaching him to settle down because as soon as they reward him he gets super hyper again.
I told them they should start saying, "Go lie down!" (quietly) as many times a day as they can, and then walking over to his pillow and dropping a treat there, then telling him "Good boy!" and giving him a release command. My idea was with enough repetitions of this he'd get the idea, but he's not the brightest dog I've ever met, so... was this good advice? Is there better advice I could give them?
I'm of course making them sound much much worse than they are, that's just my frustration shining through. The dog is relatively happy, they spend big bucks and many months of uncontrollable diarrhea to work out his sensitive digestive issues, BF's mother works part-time tutoring from her home and the dog comes in the office with her while she's working, he gets walks (and is perfect on leash) and gets to run around in the yard while she's gardening... etc. etc. etc. They just don't really have a clue about how to teach "manners," and they sadly don't have the time right now to take the dog to a training class. Any advice/tips would be much appreciated!!