One of the hardest to reach places is your ceiling fan. If you are tall enough to use a chair and a dust attachment on the vacuum cleaner it is the easiest way to remove dust and not spread it around.
If you cannot reach the blades you may have to invest in a long handled dust mop. When using a dust mop you’ll find it is less of a mess if you spread an old sheet or piece of large plastic under the area you are working to catch all the big gobs of dust that will fall from the fan blades.
Recommended cleaning is at least once a year in early spring before you start to use the fan.