Book your Trans-Siberian train tickets.  When you have planned your journey, the first thing to arrange are your Trans-Siberian train tickets.  There are several ways to buy tickets, some cheaper but more effort, others easier but more expensive.          

Second class (coupe, economy class)
Second class car, kupeiny vagon. The difference with the first class is that there are 4 berths instead of 2: two lower and two upper ones. Luggage can be placed under lower berths and to the compartment above the door. The door can be locked. By the window, there is a table. Each car also has two bathrooms. 36 people can travel in such a car at the same time. 

First class (SV, business class)
1st class car, Spal`ny Vagon (SV). First class car has 9 compartments (coupe), for 2  persons each. In a compartment, there are 2 berths to sit or lie on, and a table between. Luggage can be placed under berths. Compartment door can be closed. At each end of every car there is a bathroom with WC and water basin. 

Third class (platzcart)
Third class car, platzkartny vagon. In a third class car, 54 persons can travel at the same time. Compartments in such cars are open, there are 4 berths in each plus 2 berths over the corridor. Luggage can be placed under lower berths and on 3rd berths, specially designed to store luggage. Each car has two bathrooms. Traveling in the third class is less comfortable than in the 1st and 2nd, but much cheaper.