It'd be hard to imagine Taylor Swift ever not being 'on,' especially before a performance, but in a new Diet Coke commercial, she shows what she uses to get prepared.

In the ad, a groomsman, a college student, a new teacher, a performer and Swift all have one thing in common: they use Diet Coke to help get them ready for just about anything. They're all getting ready for big moments, and what do they do first? Take a swig of the soda, of course.

Swift's red lips drink from a straw when she hears she's 'on.' The calm 24-year-old, looking elegant in a sparkly dress, responds, "Great. Let's go."

The 'Red' singer partnered with Diet Coke last year and declared it "one of the great loves of my life.” But she's not just appearing in ads and commercials for the soda -- their newest cans also contain a Swift signature and quote.

“If you’re lucky enough to be different, don’t ever change," the new slim Diet Coke can reads.

After closing out her 2014 Red Tour overseas, Swift will presumably return to the States to wrap up a new studio album, which is expected later this year.

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