I took a day trip to Warsaw yesterday and went from Stansted to Modlin then took the train to the city. Flew in at 10am and flew out at 9pm. I'm a newbie so I made the mistake of going into Modlin rather than Chopin but lesson learned. 😀
Warsaw is absolutely beautiful. The pierogis were amazing and it was so nice to explore without a ton of people everywhere. The train was easy to take and cost about £5. You can either book the train in advance or grab a ticket at one of the stands. Cash was not needed at all as they accepted the tap to pay or card everywhere.