Just don't drink it!
Tapering off soda is probably the best way to do it: try mixing in other beverages that aren't carbonated.
If, for example, you drink 5 cans of soda a day, start by cutting down to 4 a day for a week, then 3, and so on. Make it a point to drink water or any other type of healthy drink and increase those as you decrease your soda. Maybe you'll end up liking something else better that's healthy!