Emerson said self-defense should go far beyond the ability to fight an attacker. “Self-defense has expanded beyond gouging out bad guy’s eyes with your thumbs. It should be more holistic to include signature reduction — blending into environments and not standing out,” he explained. “This also applies to your social media and online presence as well. The more you ‘tell’ without talking makes it easier to target you." He also recommended that a self-defense strategy includes the ability to escape. "A razor blade and handcuff key are easily concealed and can free you of most restraints,” Emerson said. In his book, he suggests carrying both items in your waistband at all times.