The sacrifice owner would slaughter it (if he knew how), and a Kohen would receive the blood and pass it to the next Kohen in line. This continued until they reached the Kohen closest to the Altar, who would then throw the blood on the Altar's wall. Everybody sang the Hallel. If they had to, they would repeat it, but Kohanim were fast, and they seldom had to repeat the Hallel, and definitely not sing it the third time.
There were hooks on which they could suspend and flay the offerings. For those for whom there was not a hook, there were planks of wood. One could set the plank on his and his friend's shoulder and flay it.
Three groups of people were a requirement, but the third was called "the lazy group." This agrees with Rabbi Yehudah's philosophy that "The world needs perfume makers and leather makers (which is associated with bad odor). But one should strive to be among perfume makers."
Art: Potpourri by Herbert James Draper