You just captured your worst enemy...

[Ix Rebound]

Chain them to the floor and ball-gag them in a windowless soundproof room, inject them with a virus that causes extreme pain for the rest of there now miserable life, and keep them in that state for about 7 minutes before impaling them with a flamethrower and burning them from the inside out until they are reduced to ashes.

Depending on what they did, I personally would leave them for a bit longer than 7 minutes

The way I see it, if you've seen someone screaming in absolute agony for 7 minutes, you've pretty much seen them scream forever. Plus, I'd prefer to end it on a high note, hence the flamethrower.

Fair enough I guess

 

[shootthebandit]

Heres what you do. You put your victim in a lightproof soundproof room and you leave them there with this playing on repeat (see video). Because the room is empty and assuming its padded they will eventually be forced to kill themselves using nothing but there own body

 

[NSGrendel]

Just a moderately sharp knife and as much time as I want will do.

 

[C F]

Well, I would make some comfortable living quarters and see to it he has proper and extravagant amenities. If he needs anything, he can just ask me or the supervisor I left in charge of keeping an eye on him. The request can be denied if it is unreasonable. He will have the authority to turn away or accept visitors. The supervisor will have veto authority. I will have higher veto authority than the supervisor.

At some point in the future, I may choose to let him free, or simply transfer the ownership of his living facilities to him if he has no better arrangements.
There are no other stipulations.

You see, Escapist. Unlike my enemy, I am a gentleman.

 

[EightGaugeHippo]

Step one: Tie them to a chair.
Step two: Punch them to death.

It'd be so much more satisfying and personal to use my own two hands..

 

[stormeris]

I'd tie them up to a chair.
And force them to watch Baby Geniuses. ALL OF THEM

MAUAHAHAHAHAHAHAHAHAHA

Then maybe Batman and Robin, because i'm a sick person. SICK I TELL YOU