Using a headlight, and standing to either side of your horse's head, place downward pressure on the poll using either your fingers or the halter. Your horse should drop their head downward. Release pressure on the poll, but be very ready to immediately reapply it if your horse begins to raise its head. Slide your hand toward the base of your horse's ear. Touch there. Stop if your horse is relaxed. Apply pressure if your horse raises its head.

Now, touch the main outer part of the ear, the pinna. If your horse allows the outside of the pinna to be rubbed, then gently separate the hairs on the inner surface and look down into the external canal as far as you can.

Look for masses, lumps or bumps, white plaques, and ticks or mites on the inner surface of the pinna. A brown waxy coating of the external ear canal is normal for horses. Some have more than others. Pus is never normal.

Apply a treatment to your horse's ear per your vet’s recommendations.

Teach your horse to accept your evaluation of their ear before it is necessary.

The following is the best way I have found to determine whether a horse is really experiencing ear discomfort or pain, or is merely bluffing its handler. This is also a way to desensitize a horse to reactivity.

For the left ear: Position your body at the horse's shoulder. Hold the halter with your left hand. Place your right hand on the horse's cheek. Hold your hand gently but firmly against the skin. Now (over about 3 seconds) slide the hand toward the base of the ear. Keep your hand in position until the horse relaxes, and then immediately remove the hand.

Now repeat, this time moving closer to the ear base. Walk the horse forward a few steps, interact with them, reward them with a pat, go to the other side and repeat.

If the horse tries to evade, raise or shake its head, keep constant contact with the flat of your hand and on the nose band, until the horse yields, then release both pressure on the nose band and on the face. Follow the horse's head around if necessary, maintaining the same contact with the hand on the skin and pressure on the nose band.

The second the evasive behavior stops, release pressure, interact, and walk forward a step, let them relax. Work your way up and onto the ear using this same technique. Once you get through the "bluff phase" you can better tell whether the horse really is experiencing discomfort or the behavior is simple learned evasion.