How do we navigate by seeing a crescent moon? (:-) I know)?

Question

How do we navigate by seeing a crescent moon? (:-) I know)?

Answer 1

Since a waxing cresent will be setting in the West shortly after sunset, and a waning cresent rises in the East in the morning shortly before sunrise.  Then you can get a general idea which way  East or West is based on this.

Answer 2

If the moon travels from left to right then you are in the northern hemisphere. If it goes right to left, you are in the southern.

Let's assume the moon is either pre-1st quarter or post 3rd quarter, and will also assume for northern hemisphere. If the moon is rising the cusps are pointing away from the horizon and to the right and south and you are facing east. If the moon is setting the cusps are pointing toward the left and south and you are facing west. If the moon is hight in the sky and the cusps are pointing to your right, you are facing south.