Need safety tips for cutting corrugated metal roofing with an angle grinder

Hey all, first time posting here. I'm installing some corrugated metal roofing on my shed and I need to make some cuts for vents. I've got a 4.5" angle grinder with a metal cutting wheel, but I've heard horror stories about these things kicking back or the wheel shattering. What's the safest way to do this without ending up in the ER? Should I be clamping it down somehow? Any specific PPE you'd recommend beyond the basics?

OP, listen up - this is serious business. First, ALWAYS wear a full face shield over safety glasses. Those cutting wheels can explode and send fragments everywhere. Make sure your grinder has a guard properly installed - no 'zip cutting' without it. Clamp the metal securely so it doesn't vibrate. Go slow, let the tool do the work, and keep both hands on the grinder. And for God's sake, unplug it when changing wheels. Seen too many sparkies get careless with these.

Mark's not wrong about the face shield - I've had a wheel come apart on me once and it embedded in my shop wall. For corrugated metal specifically, I'd recommend scoring your cut line first with a utility knife to prevent the wheel from grabbing. Also, consider using a diamond blade instead of abrasive - they last longer and are less likely to shatter. And yeah, clamp that sucker down tight. The vibration will make clean cuts impossible anyway.

Hey, apprentice carpenter here - just did this exact job last week with my journeyman. We used C-clamps on a piece of scrap wood underneath to support the metal. My boss made me wear leather gloves and a heavy denim jacket too, said the sparks can light up regular clothes. One more thing - cut from the top of the corrugation, not the valley, gives you more control. Almost messed that up myself!