How to unlock/jailbreak my sprint iPhone 4 on iOS 6.1.3 for free and download?

Imei

The 6.1.3 jailbreak isn't out yet but when it does, download the latest version of redsn0w and you can easily jailbreak any iphone

There's no need to jailbreak your iphone to unlock it. You can do it via IMEI and it's permanent, unlock when you jailbreak it.

you'll need a new sim, iTunes and this service: http://gsmunlocklabs.com/unlock-iphone/