Dye the bleach stain with a a color that is slightly darker than the rest of the pants.This will minimize any contrast between the original color and bleach stain. Most fabric dyes are available in liquid or powder form. Follow the manufacturer's instructions.
Color the damaged spot with permanent markers. Black pants are easiest to fix with this option, although you can find specialty markers with a wider range of colors at art supply stores.
Cover the bleach stains with beads, rhinestones or other embellishments to transform your pants into a new look. Purchase these items at fabric stores and sew them on with thread and needle.
Sew on matching fabric patches to cover the bleach stain. Fabric patches are available in a variety of styles at fabric supply stores. Simply sew them on with needle and thread.