I use a liquid made just for dogs ears called Oti-Clean. I soak a couple of cotton balls in the stuff and put one in each ear. I fold over her ears and rub them gently, then I step back and she shakes them out, along with any crud that comes loose. She then lets me wipe her ears out.
I bought some wipes in a jar from a pet store. They are about the size of those little round cotton pads. I use them if there is a lot of gunk, but mostly I just use Q-tips and clean them. My dogs are good about laying still and letting me do that though. (It could be because they know they will get a cookie if they do.)