I went cold turkey and just started drinking only water. But if thats not an option for you, you could also just switch to sugar free.

Try to replace it with black coffee or tea of some sort. There's a nice bulk store near me that sells really cheap but delicious instant coffee by the gram. IIRC sodas have caffeine in them which makes them ab it addictive, withdrawals only last a few days though.

I was able to stop sodas a number of years ago, and now the thought of drinking one makes me nauseous. A helpful crutch are those Ciao San Pellegrino's, they have a tiny bit of sugar that makes them immensely more satisfying than other flavored sparkling waters. I keep my fridge stocked with the cherry and blood orange