Some general ear care pointers...
I use an ear wash to clean the ears of mine every week. Also, a drop or two of rubbing alcohol to remove any water.
Yes, pull the hair out of the ears....sounds horrible, but mine don't even flinch.
Ear infections can be the result of excess scratching. Make sure that the dog is not scratching as a result of a food alergy. (Biting paws may be another sign.)