Calling Card Rules & Guidelines
MATERIALS
Most sources dictate the simpler the card, the more elegant and refined. The plainer the card, the better and it should not glazed or ornamented in any way The card should be made of white unglazed bristol board of medium weight (Holt, 1901).
Design & Lettering
Engraved in plain black on white is the preferred style. "The perfect card shows no decoration of any kind whatsoever. The engraving is properly and fashionable done in block, script or old English lettering. Cards used in good society are engraved in black on pure white" (Watts, 1909). I am currently searching for any primary sources that explain the prevalence of the brightly colored cards found in most Victoriana and Ephemera pages.

Example of a typical colored card with hidden name

Lot of Victorian Card purchased on eBay
The Ladies Card
As a rule, a ladies card should measure 3 - 3 1/4 inches wide
by 2 1/4 to 2 1/2 inches high. Married women should always present
their name as "Mrs. John Smith", never "Mrs. Angela
Smith. Unmarried women should be presented as "Miss Angela
Smith," never "Angela Smith." Names should be printed
in the center of the card, with the at home day printed below
on the far left with the home address in the right corner.

Example of Married Woman's Card

Example of an Unmarried Woman's Card
The Gentleman's Card
A gentleman's card is longer and more narrow, the most popular
size being 1 5/8 inches high by 3 1/4 inches long. A gentleman
should present their name as "Mr. John Smith" or but
never with only initials for his first name. Bachelors may have
the name of their club or both their address and club (in opposite
corners), but never an at home day.

Example of Gentleman's Card
The Joint Card
The joint card is used for married couples as well as for daughters
who are not out in society yet and continue to call with their
mothers. The sizes of joint cards are usually 3 1/2 inches wide
by 2 1/2 inches high.

Example of Joint Card