Girls and all women who are in the house (or if there isn't a woman in the house, the head of the household), light candles to usher in each night of the holiday. See Procedure for Holiday Candle Lighting for detailed holiday candle-lighting information.
Blessings for the evenings of September 13 and 14, 2015:
1) Ba-ruch A-tah Ado-nai E-lo-hei-nu me-lech ha-olam asher ki-deshanu be-mitzvo-tav ve-tzvi-vanu le-hadlik ner shel Yom Hazikaron.
Blessed are You, L-rd our G‑d, King of the universe, who has sanctified us with His commandments and has commanded us to light the candle of the Day of Remembrance.
[Note: When reciting the following blessing on the second night of the holiday, one should have in mind the new fruit which one will subsequently be eating after Kiddush.]
2) Ba-ruch A-tah Ado-nai E-lo-hei-nu me-lech ha-olam she-heche-ya-nu ve-ki-yi-ma-nu ve-higi-a-nu liz-man ha-zeh
Blessed are You, Lord our G‑d, King of the universe, who has granted us life, sustained us, and enabled us to reach this occasion.