When someone walks into office there are countless procedures that they must get familiar with. The day to day routine, the ins and outs of using the nuclear football and launch codes. etc. Now i am sure the president gets experience for everyday he is in office but who actually sits down with him to explain all these new things to him? The joint cheifs, the secatary? how long does “bringing him up to speed” usually take does anyone know?
Bob Newhart (I think in The Button-down Mind) did a hilarious bit on the President on his first day on the job.
I imagine there is a check list for most of this stuff - get his password set up on the e-mail system, show him how to blow up Russia, get the O keys put back on all the keyboards 
- that kind of stuff.
Lots of the “day to day” stuff is handled by aides. I doubt he needs to fill out his own W-4 forms. But he has a large support staff (and needs every one of them) who explain “You get a morning briefing on the world situation at 8:00am every weekday. This is the hot line - dial 9 to get out. The men’s room is thru that door. If the alarm goes off, the Secret Service will get you to the basement.” That kind of stuff.
Thisarticle from the Atlantic might shed a little light on transition teams for you. They start well in advance and basically the man and his cabinet just breeze right in.
All major-party candidates get CIA briefings during the campaign, if they want it. Presidents-elect get a military briefing between election and inauguration, which covers a lot of stuff, including nuclear warfare options (this is done not by the Joint Chiefs, IIRC, but by other top Pentagon officials). The White House usher has a briefing about protocol, kitchen/food/entertainment arrangements, how not to break any of the antiques, etc. A wise President will also have some experienced White House hands in the West Wing to teach him the other stuff.
One of JFK’s aides told of being buzzed to come to the Oval Office shortly after the President had settled in at his desk. The aide burst into the room and JFK, grinning, asked, “What the hell do I do now?”
I would expect that a lot of that information flows the other way, too. The President tells his aides that he wants a briefing at 8:00 every morning, tells the Secret Service where to take him under what circumstances, etc.
Some pick it up pretty quickly. Others…I’ve seen it take as much as 8 years!
If you watch the seventh (and final) season of The West Wing you’ll see some of this. There were scenes showing President-Elect Santos and his wife being briefed on White House procedures on things like launching nuclear weapons, Secret Service procedures, how to operate the telephones, and picking next week’s menu.
Most are already housebroken. Sitting up and begging is only needed if you don’t have a compliant Congress. Fetching, walking on a lead and general obedience training is usually handled by the First Lady. Rolling over and playing dead is good for messing with the VP but some have taken it too far. The biggest problem that seems to take the longest is jumping up on company. The Secret Service usually manages to curb that pretty quick.
Haven’t you seen Dave?
His staff does it. 
I get that it’s a joke, but why would the O’s be missing? 
There was a story (that I believe was later discredited) that White House staffers from the Clinton administration vandalized all the typewriters by removing the “W” keys.
No, it wasn’t discredited.
<pointless nitpick>Keyboards, surely. Do typewriters even have removable keys?</pointless nitpick>
Interestingly, I’m just watching the first DVD’s worth of ‘the west wing’ at the moment, and though the first season doesn’t cover the prez’s immediate shakedown, (He’s a year and a half into his first term when the show starts,) it still gives me a sense for how much of this is done by pre-existing staff. They did have one situation already that JB hadn’t already had to deal with and was uncertain of the procedure for - ordering an offensive strike against a foreign power. Probably there’ll be others through the series.
Traditionally, the outgoing President leaves a letter for the incoming President on the desk of the Oval Office.
Cite: photograph in Clinton’s memoir.
I can understand that the “staff” or “aides” train the new President, but who trains them? It would seem that if someone (besides the outgoing Prez, who trains the incoming Prez) has the codes for the nuclear football, for example, that he could pretend he was the Prez and start a war, no?
Sorry, RS, but reality is once again displaying its known liberal bias.
The transition is actually one of my favorite episodes. Santos’ long time secretary correcting herself when she started calling him “congressman” and now gets to cal him “Mr. President.” Mrs. Santos (Helen, also a complete hottie) with a stunned silence when she accidentally wanders into the oval office. Her meeting all the help (cooks, maids, servers, tailors, etc).
Helen: Oh, no. We don’t need all this.
CJ: Ohhhh kayyyyyy…so who do you want to fire?
I also remember the scene that while Bartlett and Santos were attending the inauguration, the White House domestic staff overran the White House, packed up all of the Bartletts’ personal effects and unpacked all of the Santos’ so that the complete switch was accomplished in something like an hour.