I sent this to a friend a while back. May be helpful...
---------------------------------------------------------------------------------
A few pointers on trains...
1) Remember that when you purchase a ticket on an IC/ICE train, it does NOT mean you get a specific seat reservation. It means you may travel on a specific train for a specific distance in any unreserved seat. If you are willing and able to play "musical seats" if someone claims your seat as their reservation, then there is no pressing need to spend the extra 3-5 EUR on a seat reservation. But purchasing the latter is typically an extra step when purchasing the former.
2) IF you do purchase a seat reservation, your ticket will indicate two important numbers. The first is for the Wagen or wagon/train car number. The second is the Sitzplatz number and this is your seat number on the wagon. During the purchase process, you are typically asked several seating options:
Großraum - Main train wagon area
Großraum mit Tisch - Main train wagon area with a table
Abteil - 6-person cabin
Fenster - window
Gang - aisle
Handybereich - cell phone area
Ruhebereich - quiet area
I personally find that the "Abteil" area is hard to get in and out of and contains less room for luggage. My favorite seating is in the "Großraum mit Tisch" with either a window or aisle seat. If you want to be chatty, then pic the "Handybereich." If you want quiet or want to sleep pick the Ruhe area. Expect the latter to be library-quiet and expect people to glare at you if you are too loud for any reason (including your headphones!).
3) So when you arrive at the train station, you should have some basic information in your hand: your train type (IC/ICE/EC, etc.) and train number (521, etc.) and destination and scheduled departure time. You will need this information to determine the departure track for your train. Similar to departure gates at airports, this track information CAN but seldom changes. When you walk into the train station, you want to look for a yellow poster that displays the "Abfahrt Fahrplan" or the scheduled departures.
It looks like this:
http://www.eisenbahnfreunde-pforzheim.de/kulturbahn/img/fahrplan_l.gif
The list is sorted by departure time. To the right of the departure time, you find the train type and number and to the right of this you find the more important destinations served by the train and the scheduled arrival time at each one. Finally, the right-most number in bold is your track number (Gleis).
In the main train hall, the most up-to-date version of this information can be found on digital information boards like this...
https://upload.wikimedia.org/wikipe...fangshalle-_Richtung_Bahnsteige_26.3.2010.jpg
If you see the word Verspätung next to your train information, then your train is delayed.
4) Once you get up to your track, this is when you will need your Wagen and Sitzplatz information from your ticket if you have a reservation.
Located on the platform is the Wagenstandzeiger:
https://upload.wikimedia.org/wikipedia/commons/7/7d/WagenstandanzeigerHannover060415.jpg
You locate your departure time and train on the left Y-axis and then your wagon number on the X-axis. Once you find this, you look back up to the top of the chart and see whether your wagon will stop under the letters A, B, C, or so on. This letters correspond to the large letters hanging from the ceiling of your track.
In this example you see the leading wagon of a train on track 1 located at section B of the track:
http://boardingarea.wpengine.netdna-cdn.com/wildabouttravel/files/2012/07/IMG_1562.jpg
5) Shortly before your train is scheduled to arrive (a few minutes before its departure time), the track screen will confirm your train's information:
http://www.bahnbilder.de/bilder/frankfurt-am-main-hauptbahnhof-168073.jpg
This screen will also display any known delays or special circumstances for that particular train.
Since the Köln main station (Hauptbahnhof or Hbf) is such a key hub, I would imagine most long-distance trains will stop for at least 5 maybe 10 minutes. Otherwise keep in mind that most trains arrive and depart within 2 minutes, so I would encourage you not to dawdle.
Every once in a while, Deutsche Bahn will throw you a curve ball and do something like reverse the order of train wagons. Instead of arriving with wagon 21 (under A) and ending with wagon 29 (under D) they will be in reverse order and the chart I described in #4 above has to be looked at backwards. This situation is the exception and not the norm.
If this is the case, the track screen will display "in umgekehrter wagenreihung" like this:
https://farm4.staticflickr.com/3200/3029743140_58a1c69dbe_z.jpg
The point is to simply get on board as soon as you can and then find your seat. Typically it is not a problem to walk the length of the train from within to find your wagon/seat.
6) Once you are in your seat, you can confirm the stops/arrival times along your journey with the Fahrplan.
7) I think I told you this before, but there are two ways of getting from Cologne to Frankfurt by train. One is the direct way that takes about one hour. The other takes you along the Rhine, through Koblenz and takes about two hours. The latter is scenic (more castles and wine country) and the former lets you go as fast as the ICE can take you (350 Kmh or so). Pick your preference.
8) If ever in doubt, just ask! Just about everyone should speak English but it never hurts to ask, "Entschuldigung, sprechen Sie Englisch" which translates to "Excuse me, do you speak English." Please and you're welcome is "Bitte" and thank you is "Danke."
Ja - Yes
Nein - No
Guten Morgen/Tag/Abend/Nacht - Good morning/day/evening/night
Wo ist die Toilette? - Where is the bathroom?
H = Herren = Gentlemen
D = Damen = Ladies
Ein Bier vom Fass bitte - One beer from the tap please.
Hallo - Hello
Ich heisse - My name is
Wie heissen Sie? - What is your name?
Ich komme aus - I come from
Aufwiedersehen - goodbye
Ausgang - Exit (Notausgang - emergency exit)
Eingang - Entrance
Wieviel kostet das? - How much does that cost?
Drücken - To push (on a door)
Ziehen - To pull (on a door)
Erdgeschoss - Ground floor
1. Stock - First floor - floor above the ground floor