The width of your finger tip, held at arm's length, is roughly one degree of arc. The knuckle of your thumb represents about 2°, and the width of your fist about 10°. The distance between the tips of your thumb and little finger, spread wide, is around 20°.

The Moon is roughly 1/2° across, and the Pointers in Ursa Major are about 4° apart.

Inconstant Moon