Monogram Ettiqutte

Single Female: First LAST Middle, with the middle initial larger than the flanking initials.
Married Female: First LAST Maiden, with the middle initial larger than the flanking initials.
Single or Married Male: First Middle Last, with all initials being the same size.
Married Couples: If you are combining the letters of to people's names, it is referred to as a duogram. If you do want to create a duogram, remember the "ladies first" rule and place the initial of her first name in the first space. Use the lady's first initial, Married Last Name in the center, and the husband's first initial.
Engaged Couples: We recommend a duogram incorporating the couple's first name initials only. It is not appropriate for an engaged couple to use a combined cypher before their wedding ceremony. Once they have completed the ceremony, they may use their combined initials.
Divorce: "As long as the new husband doesn't have a problem with it, why not continue to use it or give it as a gift to one of the children from the first marriage? It would be a shame for your beautiful monogrammed silver or porcelain to go unused." - Peggy Post
Single Letter Monograms:
 Monograms for unmarried people are often the first name initial, allowing for the addition of surname initials at a later time. Single letter monograms are prime for additional design embellishments!
Two Letter Monograms: Place the letters in FIRST/LAST order or intertwine them to create a cypher.
Three Letter Monograms: If all three letters are the same size, they should go in FIRST/MIDDLE/LAST order. If the center letter is larger, the letters should go in FIRST/LAST/MIDDLE order.
More Than Three Letter Monograms: Consider listing them in order or creating a cypher (an elaborate design in which the monogram is secretly encoded.)