To use the Spartan Tactical Plate Carrier, first, adjust the shoulder straps to fit comfortably. If you choose to use the optional side cummerbund, attach it properly and adjust it for a snug fit. You can put your insert plates into the designated areas. When putting on the carrier, slip it over your head and adjust the side closure system using the 'pull forward' adjustment to get the right tightness. As for maintenance, regularly check the stitching and straps for any signs of wear. If the mesh lining gets dirty, you can gently wipe it clean with a damp cloth. Avoid using harsh chemicals that might damage the material. When not in use, store the plate carrier in a cool, dry place away from direct sunlight to prevent the material from deteriorating.