Complex sentence: Quintanilla decided to sell the perfume at his recording studio store Q-Productions first, and after successful sales, Suzette Quintanilla, sister of Selena, was put in charge of sales.
Split into simpler sentences: Quintanilla decided to sell the perfume, first, at his recording studio store Q-Productions. After successful sales, Suzette Quintanilla, sister of Selena, was in-charge of sales.