Chaitra Navratri Parana is performed on Dashami Tithi during Chaitra Shukla Paksha (the two bright weeks of the Hindu month of Chaitra). It is the final day of the 9-day Chaitra Navratri festival.
There are conflicting statements in the Shastras as to whether Parana should be performed on Navami or Dasami, but Mimansa (who explained Shastra) suggests doing it on Dasami. Many texts can be found that suggest Navami fasting, so they agreed with Dashamititi.
If Navami Titi has his two days, fasting should be done on the first day and Parana should be done on his second day of Navami. (Suggested by Shastra.)
As it is the last day of Navratri Puja, Bhagwati Durga Visarjan should be done after Shodhashopchal Puja.
After Puja and Bisarjan, offer the Brahmin food, gifts, etc. (as you wish). Also provides these things to her nine girls and Kanya performs her pujang.