Here is the glyph for Mercury: a little person wearing a hat, like a delivery boy.

Mercury rules the signs Gemini and Virgo.

Ancient astrologers looked in the sky and saw a strange little light that followed the Sun very closely. He would show up just after sundown in the evenings for a couple of months, then disappear! Then he would show up in the mornings just before sunrise for a couple of months, then he was gone again! This was Mercury, messenger of the Gods, who got a reputation for going hither and thither and being something of a prankster.

The keywords to keep in mind for Mercury are:
The Mind: Day-to-day communications and thought processes
Short travels and trips
Capacity for learning

Mercury’s sign shows how we communicate: do you communicate quickly (Aries), slowly (Taurus)? Forcefully (Leo), softly (Pisces)? Methodically (Virgo), or off the top of your head (Sagittarius)?

The people and things in your life ruled by Mercury are Siblings, Pets, and Machines.

Mercury rules the hands, lungs, and nervous system.