For C-Curve, place a rolled up blanket behind the lower back for extra support. During this class our feet are flat and our legs are squeezed together, this helps to engage the lower core. Lean as far back to feel the quiver in your abs but not so far back that your core switches off.
If you feel any pain in the front of your hips, extend the legs long.
Pull the belly in toward the backbone.
Remember to breathe, inhale through the nose, exhale through the mouth!
These classes specifically focus on strengthening the core and therefore are not suitable if you are pregnant. Instead, give Weight For It Pilates a try!