Chitra Pournami is the important function for females. They are meant this day for worshiping Chitragupta. 

Chitragupta was born to parvathidevi through a painting (chitira puthiran). Later he entered into the uterus of Gomatha Kamdhenu and born on other chitra pournami and got the name chitra gupta, who is the assistant to yamadharma in accounting one's Papa-Punya karmas. 

Worshipping him with chakkarai pongal and other things without salt will give immense pleasure to the whole family throughout the year.

NOTE: One should avoid taking milk and milk-products on that day since he came out from kamadhenu. (It is preferrable to take buffalo milk if available). Then after finishing usual pooja and naivedhya, we have to donate rice, vegetables, dhal and dakshina in a "MURAM" .

Also some people draw a kolam (padi kolam) with the south side alone leaving empty as a mark of entrance to him. After finishing pooja they will immediately wipe the kolam. 

Worshipping Ambal in pournamis is a very special thing. Chithra pournami is famous for Meenakshi amman and Kallazhagar also. So, worshipping them also will be fruitful to us.