Avoid using bars of hand soap to wash clothing. Bar soap designed for hand washing contains a high level of fats and oils (it binds the soap into bar form and leaves a residue that moisturizes hands). These oils make bar soap ineffective at removing body oils and odors from clothing. Instead, grab the shampoo! Unlike bar soap made for hands, a hotel's complimentary shampoo should do a decent job of washing clothing, removing body oils and odors, and washing clean without a residue. Although this tutorial does recommend detergent bars for frequent travelers, these bars are compacted detergents, not hand soap, that are specially formulated for clothing.