To set up the SkyDrive synchronization, please first set up your SkyDrive accounts in the Accounts settings form:
Then log into your Windows Live ID account and select what you want to sync.
You may configure as many SkyDrive accounts as you need.
NB: Currently due to OneNote 2013 format problem you may sync only those OneNote notebooks that are only stored on SkyDrive (neither edited nor opened). Soon this limitation will be removed. To restore the 2010 format state of your notebook, please use this instruction or contact our support team.