To stop the pain of swimmer's ear, put a cup of salt in the microwave for 2 to 3 minutes. Use coarse salt and dump it into a thick sock. The sock is to prevent burns. Apply the sock to the painful ear and it draws fluid out of the ear, and improves circulation - which will help reduce swelling and its pain.
Use an ionic hair dryer, on a low setting so that it will not burn the skin, to dry as much moisture as possible inside the ear. Keeping the dryer moving will also help to keep the ear from feeling too hot.
Put a few drops of rubbing alcohol and a few drops of 3% Hydrogen Peroxide into each ear, one ear at a time. Keep the solution in for 10 minutes or until the bubbling stops. The hydrogen peroxide acts on any germs, and the alcohol will cause water to evaporate.
You could also use a mixture of half Rubbing Alcohol and half vinegar (regular white vinegar is fine here). If there is a lot of pain with this, thin the vinegar with water instead of alcohol.
NOTE: Do not put liquids into your ears if you now have or have ever had a ruptured or perforated ear drum. For that, you can use a hair dryer on low heat to dry out the ear - make sure it is not hot and keep it far enough from the ear so it doesn't burn. Then you can put the vinegar and alcohol mixture on a Q-tips cotton swab and gently wipe inside the ears. Do not push the q-tip in deep or hard - be very gentle.
You may have to do this for several days, and do it one more day after you think her ears are cleared up.