Determine your needs and your baby's age. If your sling will be used by more than one caregiver or you expect to use it as it your baby grows, look for an adjustable sling, such as a ring sling. If you have an older baby who enjoys seeing the world, consider a pouch-style sling. Wraps are the most versatile slings and can hold infants as well as toddlers. Stretchy wraps are easiest for use with newborns.
Consider your comfort level with sling-tying and sling-wearing techniques. Pouch slings can be worn in only one way -- over one shoulder and under the other arm -- and are easiest to wear. Ring slings provide easy access for relatively discreet nursing. Wraps, made of a long strip of fabric, must be tied by the user; doing so safely and securely can be complicated.
Evaluate your back strength and physical comfort needs. Sling styles vary in how they distribute the baby's weight. Pouch slings can be uncomfortable for long periods of wear, because the baby's weight is carried by one shoulder. Wraps distribute the weight evenly, making them comfortable to wear, but the amount of fabric can be cumbersome. Some ring slings have padded shoulders and edges, which can make them easy to wear for long periods.