Take purchasing train student tickets on a mobile phone as an example. The specific steps are as follows:

1. Open the mobile phone's standby desktop, find and click the "Railway 12306" app.

2. Enter the correct account number and password to log in to "Railway 12306".

3. After logging in successfully, return to the home page, select the route and date you want to take, click "Student Ticket", and click "Check Ticket".

4. Select the flight you want to take, add passengers, and purchase student tickets.

5. The system will automatically detect whether you are a student. If you are a student, you can purchase it directly. If not, you will be reminded.