Vertimas - Švedų-Ispanų - Lev ditt eget liv, för du ska dö din egen död

Pienso que no está utilizando el pasado, en lo personal creo que la traducción sería (aunque pareciera redundancia): Vive tu propia vida, porque tu morirás tu propia muerte.

tal vez "porque te vas a morir tu propia muerte"

The spanish phrase implies that in order to die ones own death it is necessary to live ones own life.

That's not what the english phrase says. It says that you will die your own death no matter what and so, why not to live your own life?

Yes. för here is the shorter form of därför: because

And ska is a particle that denotes future tense.

The connecting word is incorrect - it's not "in order to"; it's "because you're going" (at least in the English.

för and because seem ok - and also porque is ok to me