Since the Kohanim were busy with the Temple service, they could say only the absolutely necessary prayers. At the command of the appointed Kohen, they would say the blessing before the “Shema Israel” prayer, the one that deals with the study of the Torah, then the Ten Commandments, then the Shema itself, then the blessing for the Divine acceptance of the Temple service, and then the blessing of the Kohanim for the people. Then they went back to the service.
The appointed Kohen told them, “Those who are new to the incense service, come and draw lots” – since this service was conducive to riches. After that, all of the Kohanim would draw lots for bringing the sacrificial limbs to the fire (these limbs were previously left on the ramp). Some say that six Kohanim won that, and some say that it was one Kohen. Rabbi Eliezer ben Yakov says that the same Kohanim who put the limbs on the ramp now carried them to the fire.
The non-selected Kohanim would return their holy garments and dress into their own. Those who continued the service brought the incense and the limbs, and then one of them threw a specially designated shovel on the floor, whose sound signaled for the Kohanim to go prostrate in the Hall, the Levites to start singing, and Kohanim who became impure to stand at the eastern entrance, either to preclude suspicion of eschewing the service, or to shame them into being more careful in the future.
Art: Ludwig Deutsch - At Prayer