When you should get to the train station in order to catch your train varies depending on a couple factors. As a general rule, it's a good idea to arrive 20-30 minutes before your train's scheduled departure time so you can get familiar with the station, find the information monitors as well as find your platform without being in a rush.
Note that for any of the following situations, you'll need to allot additional time to visit a ticket window or a self-service machine:
- If you've got an e-ticket PNR that requires a printed ticket as instructed
- If you've got a ticket or rail pass and need to buy a seat reservation
- If you've got a rail pass that hasn't yet been activated