What can I soothe my dogs ears with from home until I can get to the vet

It really depends on what the problem is. Itchy ears can be a sign of so many things from infections to mites to allergies.

If there is a lot of hair in the ear pluck it or trim it short so that the ear canal can breathe and clean away any wax or build up.
Keeping the ear cool and clean usually helps with all the problems I mentioned above (or at least eases the itching a bit).

You can buy ear cleaners but they will not help if it is mites or an allergy. Best to just try and make her comfortable until a vet can confirm the problem.

You can try bennadryl to help sooth the itch (make sure to call a vet about proper dosing), adding some extra oils (omega oils) can help sooth allergies. Taking a warm cloth and cleaning the ears out can also help with the itchy-ness.