Tell them before the next schedule you have decided to go another way. It’s simple :) and you are willing to work the rest of the posted schedules. That’s very mature of you. I can’t even begin to tell you in my 7 years of how many people just don’t show up or say they got another job and we have to find coverage for all their shifts. New jobs know they usually have to wait for the 2 weeks because it’s proper to give a manager some time. So during the interview process they understand when you say you need to give a 2 week notice to your current job. It’s very polite. It always works out. Don’t worry. If you have stock make sure you sell it before you’re done and use your sick time I’m not sure if it’s paid out. A lot of partners just call off for the last week or 2 to apply the sick time tho I have found depending on the manager.

I went with “Hey the 15th will be my last day, I got another job” and she was super chill about it