Gymnastics
The headstand, although not an "official skill" is used in gymnastics as a precursor to many skills such as the handstand, headspring, etc. A gymnastics headstand can be done in any way; head only, head plus forearms, or head plus hands. Although it is often entered via a press, it can also be jumped into, although this is extremely dangerous. To have perfect technique, you should get both your hands and your head in a triangle shape, then kick up and point the toes.
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