Define "panic"? Does she rear, run off, swing her leg, kick at you, try to bite you?
Do this in a stall or somewhere small, safe and secure. Have a strong assistant, one who can moose her around if needed(or one who knows the right pressure points), hold her. Have her next to a wall, and even though I don't like it very much, maybe backed up to one.
Have your assistant hold her, that way you can work with both hands and free to jump out of the way if needed, and your bum will be safe from nips.
Start working your way down, and press the chestnut or the fetlock or however you ask, and ask her to pick it up. Don't anticipate a reaction(but be prepared to move). If you press the chestnut, I have found, it helps to make them unlock thier knee(which is what you want). If that happens, good. Stop, and praise gently, and then ask again, this time, ask to hold her foot, even if it is closer to the ground. Next time, ask to actually hold it. If she bends it hold it for a couple seconds and let it down. Good girl! Do the other side.
Take all she will give you for free. Meaning, don't get into a war with her. Keep working with her consistently, and don't get angry.
Stay as quiet as possible in your demeanor, both you and your assistant. If she freaks out, do your absolute best to not change the tone of your voice.
Being able to handle thier feet is one of my TOP things that a baby must learn. You will have a better relationship with your farrier that is for sure.