I don't know if normal people dream about the first thing they want their dog to learn. Or if people have thoughts about it, and then those dreams fall by the wayside, when they learn that things like "Sit" are learned far more quickly than, say, bite inhibition.
Really, I lucked out. When Elka came home as a puppy, her default behavior was to sit.
Every time she did, I made a big deal out of it. Not a sudden loud big deal that would freak the puppy out and send her fleeing the room, but enthusiastic praise ("Good sit, Elka. That's a good sit!") and, of course, treats. We believe in treating early and treating often in this house. With the apparent rise of pet obesity in America, this is something to pay attention to, but apparently Elka's metabolism is in fact a nuclear reactor, and we try to be fairly smart about what we give her, and she hasn't yet had to "lose weight". Her training treats tend to include chicken and hot dog, though she also in fact love carrots and green beans.
Once Elka got the word "Sit", a hand signal was also added. There are web sites that will show you hand signals that are used in dog training, but I kind of made mine up. "Sit" is essentially a closed fist, held horizontally. Teaching this works especially well if you are teaching "Sit" by the "Luring" method. To lure a dog is to use a treat to get her into the position you desire.
So, to lure a dog into "Sit", you take a treat, preferably a sort of smelly one, in your closed hand and hold it above the dog's head and back a bit. The nose comes up, the butt goes down. This is fun, sort of easy, and definitely the least forceful. It's a neat thing to watch a dog make a connection between what she thinks you want and what you actually want. You can also use part of the lesson to introduce words like "gentle" or "don't grab", if the dog begins to nibble at your hand for said treat. A dog who learns not to grab treats is a dog who tends to be reasonable about things like not counter surfing and not knocking children down for ice cream. She will also be a dog who you can in fact hand treats to without worrying about your fingers or the fingers of others.