To make clip art, first find a photograph of the image you want to use. Open a blank document in Illustrator, and load your image. Choose the menu from the Layers Palette, and then choose Template. Create a new layer, and choose the Pen Tool from the toolbar. Trace the image's main features. Use color and gradients to fill each traced shape and form a complete picture. Use Outline Mode to reference the original image whilst coloring.
Original images should be as large as possible. Simply searching the Internet and using an image belonging to another person may cause legal troubles. When possible, images should be photographed by the user.
To make the final process easier, load the original image into Photoshop, and indicate the color mode needed. If the image is being printed, mode CMYK should be used. If the image will be used on the Web, code RGB is appropriate. Indicating the color mode makes it easier to correct colors once the image is loaded into Illustrator.
When tracing the image in Photoshop, turn off any fill colors being used by the Pen Tool. Instead, use the stroke color in black. Use the Convert Anchor Point Tool to correctly form shapes while tracing.