Pour it into the pan in which you will make the cake and spread it with a spoon.
Let me tell you about the pan. I used a springform cake pan with removable sides (28cm) and I had problems with it. During the baking, the caramel and the juice leaked in the oven, so I had smoke and fun afterwards.
So choose a leakproof tray or pan or place the springform pan on a flat oven sheet. It will leak, but not in the oven, at least. It's easier to wash the sheet than the oven :)