Our lhasa-poodle mix had hairy ears, and our vet showed us the same as yours did, to hand-pull the hair. You're doing this the right way, a little at a time, and touching ears on other days. It's best for all involved to do a little at a time rather than a lot when it becomes a problem. It's a lot less painful to pull a few than a lot, and if your dog ever gets inflamed/infected ears, it'll be terribly painful to pull a lot of hair. Prevention is the name of the game here.

DH would pull her hair while watching tv, just a couple quick tugs then a treat or some love/attention. She was generally good about it, as she got elderly it wasn't as easy. We also used forceps/clamps occasionally, it was easy to set the clamp on some hair, give it a twist and yank. It hurt her more though, as we usually pulled more at once that way. You can also get deeper in the canal with forceps (gotta be very careful you can also pinch the tender flesh in the ear, don't ask why I know this).

It's a good habit to get in, hairy ears can have problems.