do you have a ceiling fan duster? is it a regular ceiling fan or one of those weird shaped ones? if you can get a chair or something to stand on and get some dusting cleaner on a rag or whatever you want to use i use the swiffer duster cleaner it smells good and it cleans really good! i hope this helps!
If mine gets too dusty I actually disassemble it and wash it then put it back up and then I just maintenance clean it with a damp cloth. I have one that gets dusty really fast and if I don't keep up with it its awful.