If I have the psp system version 5.03, and i don't have custom firmware how do...

You can use the Pandora's Battery, which is the safest method, as you can't really mess up the PSP (the battery itself is also an unbricker)

Here's a guide I found by googling it, there are many others if you search

http://geekindisguise.wordpress.com/2008/08/03/howto-install-custom-firmware-on-psp-slim-lite/

You can use the Pandora's Battery, which is the safest method, as you can't really mess up the PSP (the battery itself is also an unbricker)

Here's a guide I found by googling it, there are many others if you search

http://geekindisguise.wordpress.com/2008/08/03/howto-install-custom-firmware-on-psp-slim-lite/

i think your psp it to high to do it
maybe the pandoras battery

check out dark alexs affiliates see if they have what you need

Be careful you dont brick it though