Upgrading iOS other than current apple is signing

Hello, I just want a confirmation concerning the upgrade to a previous iOS than the one apple is currently signing. I am to get tomorrow an iphone 4s which is on 5.1.1 (jb-ed) and want to upgrade to 6.1.2 and jailbreak with evasi0n. It's been a long time since I messed with iphone but I remember that you take the shsh blobs (using cydia - since it's already jb-ed / tinyumbrella / ifaith), change the hosts file to point to saurik server, enter DFU mode and click-restore the 6.1.2 downloaded firmware. Is the above procedure correct? Am I missing something?