Final answer:
To make a snow angel, lie flat on your back in the snow and move your arms and legs back and forth in a symmetrical pattern, which is analogous to conservation of angular momentum in physics.
Step-by-step explanation:
The principle arm movements required to make a snow angel involve a symmetrical pattern. You lie flat on your back in the snow and move your arms and legs back and forth. To create the wings of the angel, you sweep your arms from above your head down to your hips and back up again, while at the same time you open and close your legs to create the gown portion of the angel. This motion should be done simultaneously and smoothly for the best angel appearance. These movements on snow can be related to principles of physics, similar to the conservation of angular momentum illustrated in the given figures where an ice skater changes their rate of spin by extending or pulling in their arms.