A cracked rib can take at least six weeks to heal, and there isn't a verifiable way to speed the recovery time. The only treatment options involve managing the pain, according to WebMD.
To help manage the pain, use ice on the rib, get plenty of rest, and take pain medication. Also cough or take a deep breath at least once an hour. While it may seem strange, lie on the injured side, recommends WebMD. This allows inhalation of deeper breaths. It was once common to wrap the area, but doing so can prevent deep breaths and may lead to pneumonia or lung collapse.