If you are ready to begin weaning, then you may want to wean directly to a cup. This avoids having to wean your son from breast to bottle then from bottle to cup. The weaning process could be gradual and may take months. For a smooth transition, replace one feeding a day with a cup of breast milk and gradually work your way up. Start by replacing his midday feedings, since morning and evening feedings tend to be a relaxing and comforting time for a mother and child. It may be a bit more difficult to drop out his overnight feed. Also, avoid trying to use a cup when your son is very hungry because he may become frustrated with the new object.
When children are over one year of age, they can move right to whole milk. As you probably already know, breast milk is very beneficial in terms of the nutrients it provides compared with whole milk, so the longer he drinks your milk the better. During the weaning process, your breasts are likely to feel engorged. To relieve engorged breasts, it is recommended to use a breast pump to collect the milk and then use it in a cup.
Early on in the breast-to-cup weaning process, your son may see the cup as a toy and will likely throw it and examine it before he actually starts to drink from it. Use either a trainer cup that is equipped with a snap lid or a small plastic cup. Initially using a small amount in the cup will prevent large spills. The trainer cup may hold more liquid, but it will only be a short time until your son learns how to open the lid and dump out the contents.