Pick it up (two hands as it is heavy) and shauffle it around to the boot (have the boot lid open before to make it easier) and voila !
If you wan the car to work though - you will need to run some heavy duty long leads to it in the boot. (Cheapest is to get some HD welding earth wire from a welding supplies shop), as well as a battery box from someone like supacrap or autobahn. You could leave out the box and just clamp it to the floor, but it may spill acid and anything you put into the book could arc it out - saw an autocross car on a trailer burn down a few years ago due to the jack handle weaqring through the battery box and arcing the battery out to the fuel tank...)
Also preferable is to make up a tray or frame for it to sit in in the boot... Usually where the side tank or wheel was located, but your car - your choice.. Dont forget to rehook your main loom positive feed (including you fueable link) to the starter positive (where the big long HD lead also goes to) and Voila - you battery is moved AND you car works (hopefully!)