During the morning puja, or worship, the Deity or a salagrama is bathed in pure ghee. Srila Prabhupada once explained the festival this way: "Krishna was just a toy in the hands of the Gopis, so one day the Gopis decided that we shall decorate Him. Pusya abhisheka means a ceremony to decorate the deity profusely with flowers, ornaments, cloths. After there should be lavish feasting and a procession through the streets, so that all the citizens should see how beautiful Krishna appears.
(Krsna-priya Devi Dasi, Vaisnava Academy - Alachua)