how do i downgrade to 1.5 from 2.5

hi guys
i am new, have got a psp with 2.5, i have been told that i can downgrade to 1.5 and then play games via memory card, which i got a 2gb card, just dont know how to do this, i am not technical, so will need step by step guidance, please help:confused:

You can run homebrew via the ebootload straight off the memorycard, no need to downgrade to 1.5

sorry, but how do i do that

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