It is the celebration of lord ganesha birthday which falls on the fourth day of the suklapaksha of bhadrapadamasa according to hindu calendar. It is the day Lord Shiva declared his elder son Ganesha as superior to all ganas. On this auspicious day people worship Lord Ganesha in varada ganapathi rupa and performs vratha.
Timing: According to ganesha purana, vratha has to be started on sravana sukla chaturthi, continued for one month, which completes by bhadrapada sukla chaturthi. But now a days, people of different cultures performs vratha differently. People performs this for one day or three or five or seven or ten days, starting from the day of ganesha chaturthi.
Puja: Wakeup early morning and do bath, then make a wish to perform this vratha. First make a stage, decorate it with flowers, fruits, leaves and place ganesha idol on it.
Avahana: prąy Lord Ganesha with faith and dedication and invite him into his idol which can be made by gold or silver or clay.
Puja proper: Shodasopachara puja(16 ways of paying tribute), patra puja with 21 types of herbal leaves has to be done. Offering garika(durva) is most important one in ganesha puja. Throughout the ceremony ganesha stotra, mantras are chanted.
Naivedya: coconuts, jaggery, sweets like payasa, laddus, different fruits and modakas. Modakas are most important in naivedya.
Nimajjana: After completing vratha, ganesha idol is taken through the streets in a procession accompanied with dancing, singing, then immersed in a pond or river or sea.
Mahatya: Varada ganapathi fulfills all the desires of those who performs this vratha and removes obstacles in one's spirtual and materialistic world.