Editor’s note: Up to now, Natalya Lucas has authored the blog posts on the Teen Exec website. I’m inviting my dad, Jeff Lucas, to contribute periodically as a guest writer, sharing some of the marketing principles he teaches to college students and showing how they can be applied by teens.

If you’re like me, time can feel flexible, maybe even limitless. I’ve got classes, extracurriculars, friends, other commitments outside of school, and sometimes it feels like I could say yes to all of it. But here’s the truth: even though it doesn’t always feel that way, your time is limited.