From the Airport:

Take I-70 West to I-270 South.  Take I-270 South to Exit #9, Manchester West.  Stay on Manchester Road going West passing the Barrett Station Road, Mason Road and Manchester Meadows stoplights. 
Turn right on the next street, Consort Drive, turn right into the first parking lot.

From Downtown St. Louis:

Take I-64/US-40 West to I-270 South (Exit #25).  Continue South on
I-270 to Exit #9, Manchester West.  Stay on Manchester Road going West passing the Barrett Station Road, Mason Road and Manchester Meadows stoplights.  Turn right on the next street, Consort Drive, turn right into the first parking lot.