We did ours cold turkey. I give her a straw sippy of milk before breakfast, I give her milk during lunch, and she usually finishes it after her meal. Then I give her milk in a straw sippy with a snack when she wakes up from her nap (before dinner, like you at 3ish-4). I make that a small one to go with the snack, and then at dinner I give her another small straw sippy of milk (so like the other half of the milk). Sometimes she prefers water, and she is fine until the next morning. But, that is the end of milk for the day. After her bath, I always offer her a sippy of water while we read books if she wants it. The cold turkey method worked well... I just made sure she was really good at sippys before switching all 3 bottles over.