Making this a photoset so it’s rebloggable.
I’d recommend gesture drawing out a skeleton. This works for both digital and traditional, though for traditional you can actually measure stuff easily.
Legs are essentially rectangles and half-circles. They do have some bend in the components to them, but it’s mostly a matter of lining them up. Try to keep the skeleton limbs the same relative length— doodle it out in gesture sketch format and measure to the best of your ability. Both shoulders should have the same length, the hooves should be the same size, etc. Make changes if need be, or even go straight to inking, so long as you don’t keep the errors you made in the gesture phase.
Front legs have 3 joints, and a shoulder joint. Back legs have 3 as well, which go from the hip to a subtle knee, to the hock, to the hoof. Show style has the torso partially in front of the hip, though personally I typically draw the hip overlaying the torso instead. (I didn’t here because this was more educational, and it was forward facing enough to look fine either way.)
One other thing that’s important: you may want to omit parts if the image is feeling cluttered. For instance, here I can remove the back left leg for the most part and just fill that one gap in with color.
I’ve also noticed a lot of artists tend to draw the torso fairly long. Ponies have short bodies. Drawing them long can be a style choice that heightens intensity/realism, but if you’re going for a cute style, or show style, keep the torso fairly short.
And again, I can’t stress how important gesture sketching is as well.