This trick let you cool down a clothes iron in a very quick, simple and safe way: just place it on a cool stove top.
The stove top will of course not be damaged, since it's designed to withstand heat. Also, a stove top is generally a safer place than an ironing board - it is generally more stable and more heat resistant. Finally, cool down will be quicker because the cool stove top absorbs heat quicker than air.
By the way, this works well regardless if you have a stove top made of glass, or the older "metal" kind of heating elements.
This method is so simple that it really doesn't need more steps, but if you cook on a gas stove you will not have a cool glass or metal surface to use. Your gas stove may still be a safe place to put your hot clothes iron to cool down, but for quickest possible solution I suggest you check out next step.
Step 1: Alternative Solution
Use an upside down cooking pot. The metal will absorb the heat in a quick and safe way.