These pullovers are very easy to wear. Just slip them on over your head. They are suitable for daily casual wear, like going out for a walk or hanging out with friends. When it comes to maintenance, it's best to machine wash them in cold water on a gentle cycle. Don't use bleach as it may damage the tie - dye pattern. After washing, tumble dry on low heat. As for sizing, refer to the size scale of S - M - L - XL. The size ratio is 1 - 2 - 2 - 2, so you can choose according to your needs. Keep them away from sharp objects to avoid snags.