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First, last (larger), middle is correct. First, middle, last is also correct. First and middle stacked on the left and last, larger, on the right is correct (nice look for men and on towels). There are even some new styles, such as newlyweds wanting both their initials with the last name initial on their table linens or other household items, with the last initial larger and in the center. Oh, if you put a gentleman's initials on a sleeve cuff, it should be on the left sleeve (where men used to check their watches), block style, and fairly small, think 1/3 of an inch at the largest. Think subtle. For a pretty alternative, try using only two initials, one on either side of an attractive design. I'm all out of ideas.
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