You don't need to do anything special, the server will recognize all existing pools in the attached hard drives.
In case your drives don't attach automatically, or you get into any other issues that you can't fix from the GUI, you can use the power shell CmdLets to manage all aspects of the storage spaces. (This is the issue I described in Troubleshooting Windows Server 2012 storage spaces)
For the reference, all storage cmdlets can be found here: http://technet.microsoft.com/en-us/library/hh848705.aspx
Edit:
I should add that you can even attach pool hard drives to a Windows 8 or another Windows Server 2012 installation, and it will see the virtual drives. I have personally tried this with Windows 8 before starting to use it, as I was concerned with the new tech.
This even works with USB drives. Suppose you have two USB drives in a single pool, and set the virtual drives to be redundant. If you unplug them and plug each one to a different machine, you will have two working copies of your original data. (of course you should put them back together or add another drive to each pool and rebuild, before having a healthy pool again)