No seat assigned train ticket

Since we are on the topic of train tickets, I would like to find out what I could have done to make my only train-riding experience in China a little more pleasant.
For some reasons, I didn't have train tickets booked in advance. When I got to the station, the last train headed for Yueyang from Wuhan was going to depart soon.
There were no seat assigned on the tickets.  I made my way to board the train and there were crowds of people everywhere.  Since Wuhan was not the starting sation, I found people lying or sitting on the floor. I could only find more spacious place to stand in.
Could I have been able to update the tickets? Any way to avoid this for the future China train travelers?

A lot of train station offer telephone reservation, for example, I call Wuhan train station 1 day in a head of time to book my train tickets, they do hold the seats for me until 10am the next morning. Chinese train station always over sell train tickets, if you don't book before hand, most probably, you will get on the train without seats. For future train travelers, I would recommend you: 1.As soon as you arrive into a city, ask your hotel or travel agency to book the train tickets for you . 2. Go to the train station to buy them. (Most of the time, you can only purchase train tickets within 3 days)

Within all faster trains in China there is a little office counter usually in the most middle car of the hard seat section selling upgrades to tickets on the train, they sell for example and upgrade from a hard seat to soft sleeper if there are any available. Everything is first come first serve so get there as soon as you have boarded the train with a ticket you want to upgrade.

One feature of Chinese railway system is overselling tickets. Book your tickets through a travel agency or at your hotel as soos as possible or you can only get a no seat assigned ticket and find yourself in a terribly chaos in the hard seat compartment where peopel and their huge baggage jam the aisle (especially in the busy transportation season like the Chinese New Year , national holiday)