Also what can I do to make my horse not afraid of the clippers in her ears???
Introduce clippers slowly and in short segments each time. Start by getting the horse comfortable with the sound of the clippers w/o even touching her. As soon as she relaxes (licks, eyes soft, head down) turn the clipper off and reward with a rub. Each time, take it a little further working closer to the ears and watch your horse's reaction closely. Every time you get any sort of relaxation response, take the clipper away for a bit and reward before you bring it back. If you get a negative response, stick with it, don't take the clipper too far away (within reason, don't get hurt) and as soon as the horse relaxes, back off (I NEVER tie when clipping until they are pros at it). This may take several days, don't rush it. Each session should get easier and easier until finally they will just put their heads down and practically go to sleep
There are also ear plugs for horses on the market that may make it a little less stressful for horse and owner.