Here's a little-known tip for those who are in a rush to catch a train but can't even buy standing tickets. If the train you want to buy doesn't have any available seats, you can follow these steps:

First, open 12306 and check the train number you want to take, including the stops it passes through. Then, try to see if there are any standing tickets available between any two stations on that route. If yes, buy one quickly. As long as you have any standing ticket for that train, you can use the manual check-in lane to pass through security.
Second, open 12306 again and purchase any ticket departing from your station on that day, preferably the closest station and the cheapest price. As long as you have this ticket from your station, you can go through security. After entering the station, immediately cancel this ticket, which will incur a 20% cancellation fee—so a 10 yuan ticket will only cost you 2 yuan.
In summary, with a ticket departing from your station, you can pass security and enter the waiting room. Then, using the ticket for that train and telling the ticket inspector that you need to board and will pay the fare on the train, you can board the train. Once onboard, find the dining car, sit down, and then find a train attendant to pay the fare.
Don’t ask me how I know this—it's because I thought the scalpers shouting at the station entrance could really buy tickets. Turns out, after paying 100 yuan, they just showed me this clever trick.
So, this little-known tip is worth 100 yuan, right?