It stops naturally. it's supposed to be a gradual process. All you need to do is to stop or Skip a feeding. See what happens if you offer a bottle or cup of milk instead of nursing. You can substitute pumped breast milk, formula, or whole cow's milk (if your child is at least a year old). Reducing feedings one at a time over a period of weeks gives your child time to adjust. Then you can stop completely when you stop breastfeeding, milk production will stop in weeks. All the best