Using your Hikelite backpack is a breeze. First, open the bucket - style main compartment and start packing your gear. You can quickly stuff in larger items and then add smaller ones. Use the padded hipbelt pockets for easy - to - reach items like snacks or a map. The external organization is great for items you need to access frequently. When it comes to sizing, measure your torso accurately to choose the right size. For the S/M size, it's for torsos between 15 - 19', and the M/L for 18 - 22'. Don't overload the backpack beyond its max carry weight of 11.3kg / 25lbs, as it can damage the pack and make it uncomfortable to carry. To keep your backpack in good condition, clean it regularly. Wipe off dirt with a damp cloth. Avoid exposing it to extreme heat or cold for long periods. Store it in a dry place when not in use.