Using your Deejo Latino Skull Tattoo knife is a breeze. To open it, simply push the liner lock to disengage it and then unfold the blade. When you're done, carefully close the blade and make sure the liner lock clicks into place to keep it secure. Always use the knife on appropriate surfaces to avoid damaging the blade. Don't try to cut extremely hard materials like metal or glass. When it comes to maintenance, after each use, wipe the blade clean with a dry cloth to remove any dirt or moisture. You can also use a little bit of knife oil to keep the blade and the liner lock moving smoothly. Store your knife in a dry place to prevent rust. And remember, this is a sharp tool, so always handle it with care, especially around children.