Here are some experience-tested procedures for rigging and monitoring audio in a variety of production situations. For details of wireless setup, and particularly for tips on eliminating RF interference, we recommend befriending the support technician at the rental house.
On a fully crewed set, sound technicians typically rig their own equipment; gaffers don't get involved except to run power cords. Even if you're a one-man show, use good gaffer practice in rigging lines and C-stands. Tape cables to the floor, and sandbag the stands to prevent them from toppling over. Make sure actors or interview subjects are aware how their cabling might limit their movements.
Avoiding the Built-in Microphone
Don't use the built-in camcorder ...