A trip to Germany for U.S citizens will require a valid passport and if you are planning on staying for more than 90 days on business you will be required to obtain a visa. Non European union members will be required to have a valid passport to enter Germany as well.
The majority of people in Germany speak German but English is spoken by many as well. Learning German is a great idea before you go, at least enough to order your meal or ask for directions if you get lost. You will find that a town that is not used to many tourists will have less English speaking locals.
When traveling anywhere in Europe you want to travel light. Only bring what you feel is absolutely necessary. If your items will fit comfortable in the overhead in the airplane then you can expect they will fit nicely in the save provided on the trains in Germany and throughout Europe.
The beautiful countryside of Germany is a delight to see but on a short trip you will be unable to take it all in. You should make a list of the more important places you would like to see and what you would like to do while there to make your trip go smoother and not to exhaust yourself. Central Germany will be more for the athletic ones who would like to ski or hike on their trip and for the more historic interests southern Germany will offer some gorgeous castle tours.
Choosing one are to visit at a time is best for your trip to Germany. You do not want to wear yourself out traveling long distances during your trip.
By staying in one area you will get to familiarize yourself with the locals and become a part of the charming town you are staying in. The vacation will feel more like a visit to home and will have you yearning for your return visit.
If booking your trip through a travel agent you can join some of the tour groups. This is a great way to travelGermany for someone who has never been and may be unable to determine what the hot spots are in the area they are visiting. Someone traveling alone might feel more comfortable in a group tour as well.
When you walk into a restaurant you will find the best table and seat yourself, and do not be surprised if you are charged for the glass of water you order. The waitresses make more in Germany than they do in the states so you can tip a bit less than you are used to. One or two EUR is considered a good tip for good service.
The grocery stores may seem a bit odd to the Americans visiting as they will be forced to leave a deposit to unlock their cart and use it, you get the deposit back only by returning the cart to location in which it was taken. You will bag your own groceries and pay for the bags you use as well. This does cut down on cost to the store and the prices are lower on the items they sell.
Be sure to have your cell phone charged as public phones are rare in Germany. There are spots to log on to the internet and make public calls but these spots are hard to find.