Chill the iron by placing its base plate in a shallow bowl of ice water.  This will firm up the plastic and allow for easy removal.  Scrape any plastic away with a dull plastic knife, plastic spatula, or credit card edge. Depending upon the hardness of your local tap water, the durability of certain internal parts of your iron, and the frequency of use, your iron may call for specific kinds of water.  Spring water is always appropriate; however, an equitable and less expensive option is filtered tap water. Note any damage, fraying, or kinks in the iron’s cord.  Damage to this area might be a potential fire hazard.  If damaged, discontinue use until the cord is repaired. Never put unnecessary stress on the iron by storing it on its side or back.  An iron should be stored sitting upright in an area where it is stable and will not fall.  This is also a safety precaution and ensures that if the iron were heated, the base plate would not be touching a cloth surface that can be damaged as it heats.

Summary:
Remove any melted-on plastic from your iron. Fill your iron’s reservoir with the appropriate kind of water. Check the power cord regularly. Store the iron properly.