Put the degree after the name only if the topic of the written communication is dealing with subject matter related to the degree. If you are discussing a personal matter in an informal piece of written communication you will not need to have degrees after a person's name.
Write the degrees after the person's last name in order of the lowest degree, such as an associate degree, to the highest degree, such as a doctorate.
Abbreviate the degrees. For example you can write a master of arts degree with the abbreviation, M.A. or a bachelor of arts as a B.A. A doctorate degree is usually abbreviated as a Ph.D. Separate the degrees by a comma.