I would tie them up to a chair or bed first and cover their naked bodies with starving leeches.
Then i would slowly break all their teeth with a piano hammer, after melting their tongues and lips with a glowing piece of hot iron. Then i would sew their mouths shut with rusty pieces of wire (leaving space to breath) and set aside the oral part of the punishment for the moment. The eyes will stay untouched at first, too, for i want them to witness their demise with as many senses as possible.
In the next step i would pull out all of their finger and toe nails with a gripper and cover the wounds with socks and gloves drenched in a honey-salt-vinegar-and 5000 red ants-dressing. For fun, I would pull out their eyelashes separately, and plug their noses with maggot-filled horse shit, which i'll gather at the farm close by, after breaking them with a baseball bat. As an instrument of constant threat and terror, i will have an assistant attach a 10000 mega volt battery to their testicles. The assistant will also shove soldering irons down their reproductive cylinders and put them on max at the same time the batteries will be charged to full power, which will be right after the assistant has rammed gigantic glass encrusted cactuses up their asses.
After that I would let them enjoy the ride for an hour and keep them conscious, while playing some Nickelback albums on full blast.
It would get even messier after that. I would cut off all their limbs with a rusty machete. One by one. The machete would be blunt to the point it couldn't even cut butter no more without the force of a madmen.
I would start with the toes. I will have to force myself through every bone and every chord, slowly, but driven by the power of justice and with a horny smile on my face. I would really enjoy this. In order to prevent immense blood loss, i will weld the wounds with a flat iron, after pouring hydrochloric acid on the mangled stubs. Once cooled down, the stubs will be covered with Myrmecia ants from the Amazon rain forest, which belong to the most poisonous kind of ants in the southern hemisphere.
Then i'll finally get to the eyes. Their precious little light balls!
I will use their little eye balls to milk giant cobras. Then I will rip them out with some tweezer (rip), before large doses of the venom will get into the blood stream, in order to prevent an early death. The holes will be covered with hot pieces of coal and the ears will be duck-taped shut with Nickelback's Dark Horse Album on a skipping cd player and shitty airplane headphones.
Now the victims are basically left with no senses and no way to communicate with the outside world. No ears, no eyes, no lips, no nose, no fingers or toes to feel shit. Their skin will be raw and itchy from all the leeches. Their are basically trapped inside their heads, alone with their guilt and Nickelback playing the theme song to the end of their lives.
Then i would find a nice cave somewhere in the middle of nowhere and leave them there to suffer until the lawd shows mercy. Then i would go home, masturbate and sleep.