The cleaning of fabric lampshades has always been one of the difficult and daunting chores for people! I was taught at a very young age by watching my mother clean hers. I assume that many people have never seen this done, which accounts for the lack of knowledge. Also I think people forget that this is a chore that needs to be done, especially around spring cleaning time!
I often dust my lampshade using a soft bristled brush wiping from top to the bottom of the shade using the long sweeping movements repeatedly until there is no more dust. While cleaning the cold settings of my lampshade, I take caution to avoid snagging any fringes. I have even heard of a great tip from a reader who uses a hairdryer to blow off the dust.
To remove the grime from the hard shades of plastic liner, I use a soft cloth since it’s gentle. I have always avoided the use of water when cleaning the fabric surface of a hard shade with a plastic lining since it is known for leaving marks on the surface of stretched fabric, and that will totally ruin the shade.
The lining fabric of the soft tailored sheds is dusted using the soft bristled brush. This is an automatic process that happens while dusting the outer surface of the lampshade.
These are just but a few tips, for more about cleaning fabric lampshades you can ask the particular manufacturer of your lamps, as most of these companies have websites and phone contacts for service.