Remember, the quicker you can get a horse to move without even having to touch the horse is going to be the most effective. If you have to even touch the horse to get the horse to move, then you're losing leadership and responsiveness. The 800 pound Morgan I retrained can physically move me around by shoving me with his head, but I only have to use a gesture to get him to kick up his feet and really move. It's clear who the winner is.
Moving the forequarters is always more difficult for horses because it's the heavier end of the horse, and they're not willing to move it so easily. But you can also move the horse's end over with just a gesture. I usually teach horses by moving them around first, hindquarter-yielding, leading, switching lead sides, and then immediately after I've done that, I stand on the side of the horse's head and make very fast pushing motions at their eye. The horse has already been moving so they're kind of in moving-mode, and they're usually more willing to move their feet away from the motions in order to get away from it. As soon as the horse takes a step away from the pushing-motion, even if it's forward or backward, immediately stop and relax. Then try again. Eventually you can keep making pushing motions at the horse's eye until she takes a step side-ways instead of forward or backward, but in order to avoid shutting the horse down, you just want to teach the horse that when you put pressure at the horse's face, the horse needs to get away from it by moving her feet.
Lunging is where all your cues come together. It can be a very frustrating exercise for a horse if they haven't learned all their yielding properly. If a horse has just learned those cues, or it's their first time lunging, go very slowly and always quit while you're ahead. If you push the horse too far, the horse will get frustrated and shut down. You start the lunge by standing at the horse's head and stepping straight back. If the horse turns to follow you (which she should), give her the shoulder-yield cue to push her back out, then with the rope in your hand, point in the direction she's facing so the slack is taken out of the rope and give her the move cue (clucking or kissing). Let her take a few steps forward on her own and let her come to a halt by herself. Then move forward and pet her to let her know she did the right thing, and repeat. When she's done that a few times, don't go up to her and pet her. Simply point again to take the slack out of the rope. If she even turns her head in that direction, stop pointing and relax, then ask again. This will teach her to move in the direction you point. If she looks like she's having a hard time understanding, it helps to take a dressage whip or a training stick and point it at her head to push her head out. This time, don't let her stop on her own. If she tries to stop and turn back to you, give her the shoulder-yield cue and keep her moving. When you want her to stop, draw the lunge line in and give her the hindquarter yield.
Only practice that for a few minutes. You'll be giving her a LOT of cues and it's a lot for her to take in at one time. The next time you practice, go for 5 minutes, and the next time, 7 minutes. Eventually she'll learn to read your cues on a dime and get really good at it. But if you ask for it all at once, or you're not very clear about your cues, you can confuse and frustrate her.