I have been asked to draw up an original black and white tattoo designs for a classmate. How much should I charge?

I think you have a few options. Ask your friend how much he would be willing to pay for what you are doing, as he may be under the impression that it is free. You can charge what you feel it is worth, or you can set an hourly charge and time how long it takes you to draw it. Bear in mind that the final product will more than likely need to prescription medications online be adjusted by the tattooist to make it suitable for skin, so you may wish to also include an outline in lead pencil on tracing paper, to make it easier to work with. Best of luck! Hope that helped.