IGN and Greg Miller walk you through the process to use two different PlayStation Network accounts on Sony's new handheld, the Vita. While it may be a long procedure, this allows you to play with as many PSN accounts as you want using one Vita.
Along with the video, here are the basic steps:
1) Sync your trophies with PSN
2) Remove the first PSN profile's associated memory card
3) Restart the system
4) Restore "Factory Settings"
5) "Deactivate" the system
6) Enter the new PSN account info you wish to switch to
7) Insert the memory card associated to the new PSN Account
8) Re-activate your Vita on the PSN
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