Om Gan Ganapataye Namo Namaha,
Shree Siddhi Vinayak Namo Namaha I
Ashta Vinayak Namo Namaha
Ganapati Bappa Moraya ||
This is a mantra from Ganapati Upanishad. One may always use it before beginning a journey, a new course in school, new career or job, or before entering into any new contract or business so that impediments are removed and your endeavor may be crowned with success.
