We did it cold turkey on our daughters first birthday. We talked about for the 2 weeks leading up to that day.
I took her to the store and let her pick on out herself.. Then I purchased one just in case.
Once I put her to sleep the night before, I reminded her in the morning, she would be 1 years old so no more bottles, she was "Going to get to use a sippy cup!" I then thew away all bottle paraphernalia so we would not be tempted to go back..
The next morning at breakfast I asked, do you want milk or juice in your sippy cup? We never looked back.. At her birthday party that day, every person also gave her a sippy cup.. she was alawys able to have a choice of cup (gave her some control) and I would ask her, milk water or juice? For different meals.