You will need -
Not as painful as you'd think and cheaper than laser treatment. It takes ages, but it get's the job done. It'll leave a scar, but it's better than a tattoo you don't want.
Sterilize, pinch with nail clippers, slice off skin with scalpel.
I would never claim that this is a good idea. I'm just saying it saves money and get's rid of that tattoo you wish you'd never had done.