Unable to jailbreak iPhone 4

[Iklaas]

Hello there,

I spent a loooooong time figuring out how to jailbreak my old iPhone. Because I don't want to discard this previously pricy phone, I want to jailbreak it to be able to use apps that still work now.
I tried Pangu, but it wants to go to iTunes first. I don't want to go to iTunes because I don't have to backup or anything else. The execution stops there.
I tried Absinthe, but it promps me to disable the password set for the screen lock. But I have disabled the password. The execution stops there.
I've tried Absinthe on my Linux and Windows machines, and Pangu (the executable) on my Windows machine (Pangu doesn't work on Linux).
What can I do to get my iPhone jailbroken? I just follow procedures as they are handed to me online; don't exactly now what I am doing to be fair.

Update
I just tried Cydia Impactor. The instructions say I should use a file called nvwastone (.ipa file) also (don't know why), but I am not able to copy it into the Cydia program. I have tried to run Cydia Impactor without using the IPA file. In the files I uploaded here you see the first and last screen doing this operation.

 

[TriJetHero]

Depends on your iOS version

 

[Iklaas]

Depends on your iOS version

That's 7.1.2. And to be more precize: i want to turn my iPhone 4 into a Linux device. I read that you can download XLinux for that in the Apple Store. But that's an embedded version. My goal is to make it entirely Linux.

 

[TriJetHero]

iOS 7.1.2 is the final firmware for the iP4, you can only use Pangu to JB it, no other tools are compatible.
So either do the backup and restore via itunes or give it up.

 

[Iklaas]

Thanks for the support!