Problem signing into Apple ID I can't sign into iCloud because the account is set up under my OLD email address and I don't remember the password. How can I change the iCloud account to new email address so that it is useable?

I am using an iPhone 5s with iOS 9.2.
If you don't have Find My iPhone enabled:
On your iPhone, go to Settings > iCloud and tap Sign Out on the bottom. Then just sign back in with your new email address.

If you do:
Go to the link below and use it to reset the password for the old email.

You can manage your Apple ID at appleid.apple.com.