We don't have a diagram for the fuel line connections on a chainsaw or trimmer. The technicians are trained on these things in factory schools.
You have one large fuel line and one smaller. This eliminates some chance for error. If you have 2 small fuel lines to the carburetor connect them and start the engine. Reversing the fuel lines will not prevent the chainsaw from starting. If you have them connected backwards, the chainsaw will start and die. Reverse them and you will be correct.
The routing of the fuel lines vary from model to model. Keep in mind that the primer bulb circulates fuel from the tank, through the carburetor, and back into the fuel tank. One line goes from the fuel tank to the carburetor, and one line goes from the fuel tank to the primer bulb, from the primer bulb to the carburetor, and back to the fuel tank.