there are lots of ideas for getting the last few bits off, but for the initial cleaning, warm the iron and run it over a brown paper bag..the rougher the bag the better..the texture of the paper bag helps pull off a lot of the gunk. Just make sure that you move to a clean part of the bag for each swipe of the iron. I've also been successful at using rough toweling rags to wipe across the iron when it's warm...but neither of these takes off all the gunk. Good luck.