Rainbow fan!  

Clean your fan completely.  I used a compass to make sure the lines were the same on all blades because that’s how I roll.  That creates distinct color blocks as it spins.  That was nice but I wanted it to be more like it is now with the blur of colors.  The messy splats created more of a smoother blend.   I just used cheap acrylics.  I’ll seal it later tonight with decoupage glue.

This paint effect works on all fan speeds on this fan.  

The lesson I see going around with a red blade, a blue, and a yellow blade on a three-blade fan did not work for me.  All I got was a blur of red.  Maybe that one will work for you too though!