A method for operating a combustion system is provided. The method includes coupling the main swirler to the pilot swirler such that the main swirler substantially circumscribes the pilot swirler, supplying fuel to a first fuel circuit defined in the main swirler, and inducing swirling to the supplied fuel via a first set of swirler vanes positioned within the main swirler. The method also includes supplying fuel to a second fuel circuit defined in the main swirler, inducing swirling to the supplied fuel via a second set of swirler vanes positioned within the main swirler, each of the second set of swirler vanes comprising at least one second fuel passage defined therein, and coupling a shroud in flow communication to at least one of the first set of swirler vanes and the second set of swirler vanes, the shroud comprising at least one third fuel passage defined therein.