Always ensure the clamp is tightly secured around the conductor, or your reading will be worthless. Plus, remember to clamp only one wire at a time, clamping both hot and neutral together will cancel each other out, resulting in a zero reading.
Before you start clamping, check your meter's rating and avoid any exposed terminals.
Don't touch anything else while measuring.
Trust me, wearing insulated gloves on high-current circuits isn’t being overly cautious.
Hold the clamp perpendicular to the wire for the most accurate readings. It’s also a good idea to test with a known load first to ensure your meter is functioning correctly. Make sure you’re set to the right mode (AC or DC) because using the wrong setting will give you useless numbers.