Change spark plugs?

I bought Autolites and was just curious id there's a trick to replacing the spark plugs. I thought it would be a little easier than it is... There's a metal round part around where the wire fits over the plug... Do you pull that thing off first or what??? Can someone please help, or at least tell me where I can go to get some information?
Thanks!

[email protected]

give the wire a slight twist from the end of the boot. That should dislodge the stuck boot from the plug without pulling the end off the wire. The metal heat shields just slip over the wire end, so try twisting them off first to give you a better grip on the boot. Whatever you do, don't yank on the wire, or you'll be buying a new set of plug wires too.