I am from Mahatashtra and my husband is from Andhra Pradesh, hence there are few cultural difference. When I went to our terrace, there was so much of moon light and seeing that I wanted to celebrate Kojagiri Poornima.
I don't remember much of the Pooja done on this day, atleast not at my home. But I remember my nani used to me that they do Pooja of Shankar Parvati idol( similar to Ganesha idol) on this day and sing lots of songs. These songs are not the devotional one but mostly they are funnier kind made on saas-bahu(mother-in-law and daughter in law)!
Most of the time we use to have our mid term exams, and hence we use to miss the the fun. It use to start with collecting money, buying milk in bulk so that each member gets a glass full, snacks ( samosa, chiwda, etc) pre planned games and some music. Around 10 pm, everyone use to gather and milk was kept for boiling. Till the milk get the thicker consistency and moon comes exactly above so that we can see the shadow on the milk, we would play different games. Games like antakshari, cards and dance would go on.
Once we see the shadow on the milk, it would be ready to drink and we could also enjoy the snacks!