Summarize:

In general, unwrapping your baby suddenly and completely doesn't work well; your baby may feel uncomfortable and struggle to sleep. If you have a very active baby who has been wriggling out of the swaddle independently, you can try this method. Otherwise, a more gradual approach is probably best. If you do choose to unswaddle your baby "cold turkey," try it at nap time first. That way, if it doesn't work out, you won't sacrifice much sleep. Many babies accept unswaddled sleeping more readily if you start gradually. Try leaving his or her hands and armed swaddled as usual, but unwrap the legs. You can use special swaddling products for this purpose, or you can improvise with blankets, cloth diapers, and the like. Alternatively, you can start by unswaddling your baby's hands and arms, while leaving the legs wrapped as usual. For best results, leave just one hand free at first, then move on to both hands. As your baby accepts each stage of unswaddling, move forward until he or she is sleeping with no swaddling whatsoever. If your baby struggles to sleep, wakes frequently, or seems upset, do not move forward. Wait until he or she can accept the first stage (an unwrapped arm or unwrapped legs) before unswaddling further. If your baby really loves swaddling, it might help to start by unswaddling only during naptime or only for the first few hours of nighttime sleep (say, until he or she wakes to breastfeed). Gradually increase the time spent unswaddled. If your baby is struggling to fall asleep without being swaddled, try gently holding his or her hands against the chest. This may soothe your baby and let him or her fall asleep. There are a number of products on the market, shaped like sleeping bags, to help babies stay warm and calm without tight swaddling. If your baby seems comfortable in one of these, use it! You can gradually unclip the sleeping bag to ease your baby into the feeling of freedom. In addition to the bags, there are also swaddling straps available that keep older babies comfortably swaddled. If your baby is struggling to sleep without his or her usual swaddling, you could consider using one of these products temporarily. If your baby wakes and cries more easily when he or she is not swaddled, try using other soothing techniques. For example, consider: singing a lullaby playing soothing music wearing your baby in a sling and walking around rocking your baby Soothe your baby as needed, but as soon as he or she is calm, put your baby back in the crib to go back to sleep. Every baby is different, and yours may take some time to accept these new sleeping arrangements.
Know that the "cold turkey" method probably won't work well. Try unswaddling your baby's legs. Consider starting with the hands. Move forward gradually. Pay attention to your baby's signals. Set time intervals. Help your unswaddled baby calm down. Experiment with baby sleeping bags. Soothe your baby without swaddling. Be persistent.