Determine the location of the stain. To know where to begin cleaning the tile, it is necessary that you find the stain. For example, the stain may be at the center of the tile.
Put some dishwashing liquid on either a wet paper towel or a wet cloth. You can use either, but a wet cloth may be better for scrubbing because it is less likely to rip.
Rub the paper towel or the cloth in a circular motion over the oil pastel stain until you see the stain fade.
Dry the area of the former oil pastel stain with a dry cloth or dry paper towel. If you still see some of the oil pastel color, put some soap on a wet paper towel or wet cloth, and rub the spot until it vanishes.