Core & Frog Hops
It's no surprise that the core plays a huge role in handstand. A strong core (both the abdominals and the lower back muscles) help to stabilize your inversions. I really like frog hops, especially as this is the first handstand variation where I found balance. Finding balance in a frog hop comes a little more easily due to the lower center of gravity and balanced weight on both sides of the body (with the legs bent outward). It's also a great way to increase the heart rate!