Yes, in order to software not digitally signed by Sony, you need to have custom firmware. There are a few ways to install it, but they depend on your currently installed official firmware. You should google for a tutorial on how to install it without a pandora battery if you don't want to buy anything, but I highly recommend shelling out the 30 bucks or so it'll run you for a pandora battery and magic memory stick. You can buy them in combos from eBay or most decent auction sites. The advantage of the battery is that it'll allow you to recover your PSP should it become bricked.