HOw can I fix Stihl fs 55r?

On a StIHL FS55r trimmer, I took the fuel lines off carb to inspect carb, and replaced the carb and lines as I thought I took them off, but I either get a whistle sound or air build up and do not know for sure how the lines connect could You let me know how they connect, either the line closest to the motor or left facing to top of carb, and farthest or right facing to bottom, or farthest from motor or right facing to top of carb, and closest or left facing to bottom?