Read more fascinating clues from the page (https://www.warsawcitytours.info/tours/one-day-cracow-and-auschwitz-tour), You will find it under this hyperlink. It contains much more details about this topic.
First, term must to be very far or really near to your booking date. Because last and first minute deals are the finest. So if you wish to go to Poland, try to find any flights to Krakow at least half a year before your journey, it is the finest way. Beside, don’t choose famous dates, like Christmas or public holidays, it is the most popular to fly then, so it should be expensive. Next relevant thing is to find any place to stay. In most of bigger metropolis in Poland, plenty of hotels are located next to the squares, the same is with Krakow (click this page). You may use your browser, or only choose any international website with services like that. You may reserve your room there, in chosen date and area, and you could pay for it when you land in the city. If you already located nice flights from London to Krakow, and booked room into great hostel, you are prepared for your adventure.
After you land in Krakow, you will need to find a cab, to go to the old town, but do not be scared it is not really costly. Next great thing, is that most of the Polish people, especially younger ones, are speaking in English. So don’t be ashamed to ask anything each people who are passing you by. First area you need to explore is old town. You will find there a Mariacki Church, magnificent Gothic temple, with breathtaking altar inside. Also, stained-glasses are worth to be seen. Not very distant from it, you should notice Sukiennice, exact in the middle of the square (visit page). This large monument use to be a market area. Today, you might buy there a lot of souvenirs from your trip. Not so far away from the square, you could find Wawel Hill. On the top of it is situated Royal Castle, former home of Polish Kings. It was created in the Middle-Ages, but it was overhauled many times. On the same hill, you could find cave, where according to legends, horrible dragon use to live. But Krakow is not only about sightseeing, it is also about fun. If you want to grab a beer at night, at the square you will find plenty of pubs with great music, delicious alcohol and friendly people.