Using this mountain bike jersey is a breeze. Just put it on like any other shirt before hitting the trails. The loose fit makes it suitable for various body movements during cycling. When it comes to the stash pocket, you can store small items like keys or energy bars, and use the sunglass wipe to keep your glasses clean. For sizes, choose according to your normal clothing size as it ranges from XS to XXL. As for care, machine - wash it in cold water with like colors. Avoid using bleach as it may damage the fabric. Hang it to dry to maintain its shape and the integrity of the print. If you want to iron it, use a low - heat setting. This jersey is built to last with proper care, so you can enjoy many rides with it.