Changing a hard seat to a hard sleeper is a common problem when traveling, especially on long journeys. Here are some tips to help you smoothly swap from a hard seat to a hard sleeper. 
First, understand the ticket regulations. Different railway companies may have different rules, so you need to be aware of the exchange rules for the train you are travelling on. Usually, hard seats and hard sleepers are different ticket types, so you will need to buy a new hard sleeper ticket. Second, plan ahead. If you want to exchange tickets during your trip, it's best to plan ahead. Some time before the train departs, you can contact the railway company or go to the ticket window at the train station to ask about the rules and procedures for exchanging your ticket. 
On the train, you can ask the conductor about exchanging your ticket. The conductor will usually help you out, but you need to be aware that the hard seat and hard sleeper may not be in the same carriage or on the same train, so you may need to leave your current carriage and go to another carriage. Finally, take care of safety and comfort. When exchanging tickets, you need to ensure your safety and comfort. If you need to change your ticket at night, it's best to choose a safe and comfortable location, such as near the toilet or carriage junction. In addition, you will need to take care of your luggage and belongings when exchanging your ticket to avoid loss or theft. Changing from a hard seat to a hard sleeper requires advance planning and understanding of the ticket regulations. On the train, you can ask the conductor about exchanging your ticket. When exchanging tickets, you need to ensure your safety and comfort. With these steps, you can smoothly swap from a hard seat to a hard sleeper for a more comfortable and safe travel experience.