★★★★★
One formula I've tried with success is as follows:
I take my finger (my pinky) and barely wet with water and dab that into baking soda. I insert into each ear. There are other ways to get a bit of baking soda (barely moistened) into ears (q-tips) but the digital way is my favorite. I let that dry completely in each ear for four or five hours. I clean the outside of the ear to get rid of the white residue but don't touch the soda deeper in the outer ear canal. I just let the baking soda work its absorbing action for four or five hours.
Then I get out my Oregano Oil and using the dropper drip one drop into each ear. Yes it stings. Some people might not be able to take the stinging so if too much I'd swish out with an ear syringe of warm water if oregano is too painful. But although it stings, I think it is killing any infection in the outer ear canal that contributes to itching.
Now in a day or two an amazing thing happens (at least in my case).... a film is emitted from each ear. I might have to reapply two or three times in a month, but my ears are free from itching and any crusty buildup.