I put a lot of info into the notes, so take your time and read them.

Burst Sona is different than normal Sona. That should be your primary thought in your head when you try this. People expect a squishy enchanter, but you can abuse that and turn the tables on them. Your primary value is getting damage off, then healing your team during and after fights. If you die early, you were useless to the team, so play for quick burst/poke during the entire game.

If you can ult half then team then burst the backline support or adc, you have done your primary job. Another thing to know is that you will do more damage than most of your team. Its what the build was designed for. Try to let them get the kills however, as a garbage Ezreal thats fed always beats an amazing ezreal who has 2 kills and 6 assists.