Dog ears are sensitive and need to be cleaned often. Here you get some tips.
First, gently wipe the inside of the outer ear, then drip an antibacterial solution into the ear canal. Massage the ear on the outside and let it work for a while, wipe the ear again. The pet store has both wipes and ready-made solutions. You can also make your own: Take one part vinegar (white) and two parts water and mix.