Sankashti Vrat and Puja is preformed for Lord Ganesha on the fourth day after Purnima or full moon of every Hindu Lunar month.
By observing this fast people pray to Lord Ganesha and impress him, as it is believed that this fast helps in removing all difficulties and obstacles in life.
It is a full day fast observed till the sighting of the moon and Sankashti Puja is performed in the evening.
If you are not able to observe a full day fast due to sickness or health problems then you can observe a partial fast and can eat Sabudana Khichadi or fruits or curd rice.
The procedure for the Sankashti Chaturti fast is mentioned below :
After early morning bath, prayers are offered to Lord Ganesha in the usual way by lighting a lamp or Aarti. After performing this the fast begins. Then in the evening the puja is usually performed after sighting the moon or as per the moonrise time given in the panchang or calendar (if the moon is not visible for a long time). After sighting the moon, an idol or painting or photo of Lord Ganesha is decorated using flowers and Durva grass and a lamp is lit. A coconut, banana, prasad (Modak) and flowers are offered to Lord Ganesha. Then the evening aarti is performed and Ganpati mantras are chanted. Special pujas are offered to Chandra or moon god. The puja involves sprinkling water, sandalwood paste, flowers and consecrated rice in the direction of the moon. After the puja the prasad and the other offering to the lord are distributed.
Mantra Chanted on Sankashti Vrat Day :
वक्रतुण्ड महाकाय सुर्यकोटि समप्रभ
निर्विघ्नं कुरु मे देव सर्वकार्येषु सर्वदा
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