If you are capable of gently swabbing the ears with a Q-tip and mineral oil, this will kill the mites by smothering them.
If you have a dog that resists and moves a lot, then i would suggest not using Q-tips or certainly not pushing them beyond what you can see.
Using an eye dropper to insert mineral oil is also a good method without the fear of damaging the inner ear.
It is always best to consult your vet before using anything in your pets' ears, or trying to treat symptoms that may be something other than what you suspect them to be.
The best rule of thumb is to never do anything to your pets that you would not do to a child. (assuming of course that one is not abusive to their children and actually care about their well being.)