Then, with your PSP charged (and preferably still plugged in to avoid battery glitches), go to the games section, select Memory Stick and then select your update.
Follow the update instructions and let it do its thing.
There are a lot of different ways to downgrade your PSP, which one you’ll have to use depends on your current firmware.
Some are harder to break than other, but it’s always possible.
Therefore, for all the speedreaders out there: So we want to install a custom firmware (m33 to be exact).