1. How do I teach my horse to move her shoulders, rib cage, and hind under saddle?

2. Where do I position my leg for these 3 cues?

I call these 3 movements my horse's buttons, and they are essential to gaining control of your horse. We also use these buttons as a foundation for other more advanced cues like bending at the walk, spins, and sliding stops :)

To start, I teach almost every under saddle exercise on the ground first. Since we start our horses with groundwork, we are working and teaching in a way that's familiar to them. Starting on the ground will help you establish a starting point with these exercises. Below I will list the key exercises you need to nail down before starting to teach these skills under saddle

-Lunging exercise

-Disengage hind at a standstill

-Disengage hind from a distance

-Yielding the forequarters from a distance

-Yielding the forequarters with touch

** All of these exercises are in my "Essential Groundwork" training series, launching soon :)

After you get all of these exercises very good on the ground, you'll need to lay some foundation under saddle

-Lateral Flexion

-One-rein stops

-Lateral Flexion

-Cruise control

-One-rein stops

-Rollbacks

-Side passing

-Vertical Flexion at all gaits 

Notice a pattern? In horse training, a lot of early exercises become the foundation to many others. Lateral flexion is seen a lot in the beginning, and as you work your way in to more advanced things, these three maneuvers will be seen a lot too! 

I would start by teaching to disengage the hind. Don't wear spurs for the teaching stage of this, just your bare heel. Remember that in the beginning, your buttons will be very spread out. Whenever you teach anything new, you need to exaggerate your language so your horse doesn't get confused. I start by laterally flexing my horse, and on the same side, reaching my heel back to the flank area. Just lightly press your calf and count to 2. If nothing happens, use the end of your mecate reins and lightly spank side to side until he disengages. You are looking for the same thing to happen as on the ground, with the lead foot pivoting and the inside back leg stepping over the outside. Don't release the pressure until he makes one right step. Once he makes a correct step, release your leg and mecate spanker but immediately bend his head to your toe and soften him before releasing his head. Repeat until you no longer need to use the mecate end and your horse can do a 360 on both sides. Then you can incorporate spurs and start refining it. Slowly start cuing him away from his flank until your cues as light as a feather and are by his back cinch.

Now let's move on to the ribcage! This is one of my favorite exercises because it gets your horses SOFT. It's great for getting their mind back on the trail, and great to soften their whole body. It also serves as the foundation for lead changes and many other awesome things. I always wear spurs for the teaching stage of this because it really helps them find a starting point. Tip- Don't start this until your lateral flexion is absolutely flawless. You will run in to a lot of trouble if your horse isn't soft through his head and neck. Start by laterally flexing your horse and also gently rolling the spur on his ribcage(right where your heel naturally falls in the stirrup) until he walks forward in a circle and bends his head to your toe. You may have to ask for less bend with the rein initially to let him know you need him to move forward. This is a hard exercise to teach and it may take some time for your horse to grasp the idea. Especially with your more lazy, cold blooded horses, it's hard for them to realize they need to both walk forward and bend their head. It takes a lot of coordination and strength! Keep at it and aim to at least get a starting point in the first lesson. Your goal is to have your horse move in a perfect circle, and when you apply the spur, his nose comes to bend in to your foot. This is his whole body following through his ribcage and neck, and it really takes softness to a whole new level. Adjust the teaching stage of this exercise to your individual horse- If he's more lazy and has trouble moving forward, ask for less bend and use your mecate rein end to get his feet moving. If he's more hot and nervous, ask for more bend keep the spur on his belly until he relaxes. Once you get the walking circle nailed down, you can practice changing arcs at a walk(setting him up for lead changes), serpentines, and then at more gaits like the trot and lope! 

Shoulder work under saddle comes much later in the horse's training, and since there's so much prep work that comes before it, the maneuver becomes sort of a by-product of everything else you teach your horse. By the time you side-pass your horse, he pretty much already has the shoulder movement down :) But if you wanted to refine it- just apply the principle of pressure and release! Set him up, cue him by the front cinch, and release once he does it correctly. You can also help him out in the beginning by applying pressure to his shoulder, since you taught that on the ground first.