The custom in some places is to recite Shiras HaYam (Song by the Sea) posuk by posuk during Pesukei D'Zimrah of Shabbos Shirah. Some say it all in unison.

--Likutei Maharich

The Shirah should be recited with intense concentration. The Medrash states that those who recite the Shirah every day with great joy and precise vocalization, imagining that they are actually leaving Egypt, passing through the sea, and Hashem is saving them, will have all of their Aveiros forgiven.

--Pri Tzaddik from R' Tzaddok Hakohain

**Please consult your local Orthodox Rabbi for Halachic decisions.**