But don't I have to set the gap with one of those fun tools?
These days you order plugs specifically for your car, and they come already gapped. I know some die-hards out there will strongly disagree (here come the e-mails) but I have never opened a new spark plug and had to reset the gap, never!
Put the plug-wire end of the plug in the socket and, holding just the extension, push it all the way in. Now carefully guide the spark plug into the hole. Try not to ram it in or bang it on anything because this can screw up the gap or damage the plug. With it sitting in the hole, begin to screw the new plug in by hand. Starting them off by hand instead of using the wrench will keep you from accidentally cross-threading one of the plugs. Screw it in by hand until it stops, then put the wrench on the end and tighten it snugly. If you have a torque wrench, you can torque it to spec, but if you don't, just make it tight without overdoing it. The metal in there is soft and can be damaged by overtightening. If you are pulling hard enough to make a sound come out of your mouth, like a grunt, you're overdoing it.
Now put the plug wire back on.
