Once that is done I recommend installing ROM manager and flashing a custom recovery (it can flash either clockwork or SPRecovery). You could also install something like titanium backup at this point to backup things that wouldn't restore automagically after a wipe, especially if you planned on flashing a ROM.
I also recommend that you let your friend do it. It is a good learning experience for him/her to do it themselves. Knowing how to reboot into recovery, how to create a backup, knowing how to restore a backup if something goes wrong, how to wipe, how to install a new ROM/theme/kernel if they wanted to.... etc If you just take the phone and hand it to him 45 minutes later, ROM'd, themed, overclocked and walk away...if something goes wrong somehow (and it can happen) he/she will be stuck. He/she may not be able to call/text you about the problem with a busted phone.