Very easy to use, just put it on and settle baby in! Folks who like this sling usually like not having to mess with anything. The nice deep pocket holds baby securely from birth through toddler. Unlike other fitted slings, the folds are centered, which means it doesn't matter which way you put it on and it is a little easier to get baby in. Sizing is based on the build of the caregiver rather than the size of the baby. I can use the same sling for my 4 month old and my 3 year old. The fabric is a 100% cotton twill- nice and sturdy without being too bulky. A little bit of padding at the shoulder spreads the weight while keeping it small enough to store in a diaper bag. For an average build, small fits up to 5'4" medium up to 5'8" large up to 6'. Colors currently available: Chocolate, burnt orange, deep red, dark olive, muted floral. Please list first and second choice colors