How to jailbreak iPhone 4, iOS 7.1.2, free & easy?

I want to jailbreak my phone but I can't find anything for free that works. Half the time it's like a scam/virus too. I have an iPhone 4, iOS 7.1.2. All comments & help will be greatly appreciated!

Just use Pangu
http://www.iphonehacks.com/download-pangu-jailbreak

Go to www.iphonehack.com