When my girls get their bath every week, I clean their ears with Vet Solutions & cotton balls. Usually, every other week...I check for any hair growth in their ears and pull it out. You can use your finger tips or a pair of forcep like tweezers.
Bella
Boo developed a yeast infection...
...I know, sounds weird...in an ear...who'd ever think you could get one there!
So, my Vet informed me that I should be keeping them clean of hair growth especially, since she has floppy ears...which can trap moisture inside...creating a perfect environment for yeast to grow.