Final answer:
Before connecting a saw to a power source, ensure the power switch is in the off position to prevent accidental starting and potential injury.
Step-by-step explanation:
Before you plug any saw into a power source, make sure the power switch is in the off position. This is a crucial safety measure to prevent accidental starting of the saw when power is connected, which could lead to injury or damage. Always check the power switch before connecting any equipment to electricity to ensure your safety and the safety of others around you.