Sketch your design on blank white paper using your regular pencil. Don't worry about shading or coloring as this point, just draw the general outline of the image. Correct any mistakes with your eraser and make sure every line is exactly how you want it before you move on to Step Two.
Trace over the pencil lines with a thin black marker, again, don't worry about shading or coloring. If you make any mistakes, start over on a fresh piece, do not attempt to continue if you've made mistakes in marker ink.
Flip the paper over and copy the image onto the back. This reverse image is what you will use to make the stencil so you want it as perfect as possible. Do this on a lighting desk or well-lit surface to ensure the lines show through. Some people use carbon paper, some just flip and trace, it doesn't matter what you do, so long as you achieve a reverse image of your design.
Tape a piece of stencil paper over the reverse image of your design to ensure no motion or separation of paper when you are tracing.
Trace over the reverse image onto stencil paper using a tattoo stencil pencil. This ink is very difficult to erase, so if you make a mistake, start over on a fresh piece.
Peel away the tape and separate the two pieces. Give the stencil to your artist and allow him to make any necessary alterations or corrections.