Margins and indenting
If you're using a typewriter-style font, your lines should have a maximum length of 6 inches, which translates into left and right margins of 1-1/4" on a 8-1/2" x 11" page. (Alternatively, you can use a 1-1/2" left margin and 1" right margin.)
A4 is the standard page size outside the U.S. and Canada. A line length of 50 to 55 monospaced characters should provide acceptable left and right margins on an A4 sheet.
The bottom margin should be roughly an inch (25 mm), with an inch and a half (40 mm) at the top of the sheet to accommodate the page header.
Indent each paragraph by 5 or 6 spaces, and do not insert extra lines between paragraphs.
Finally, don't justify your text. Editors prefer an unjustified left-aligned page, which yields a "ragged right" margin.
Opinion is divided on what should be in your page header. Some authorities recommend including your name and manuscript title on each page; others, such as publisher and writing guru Sol Stein, feel that busy page headers distract the editor from your text.
I suggest a compromise:
Durant Imboden / 2
This keeps the author's name or "brand identity" in front of the editor without getting in the way--especially if you allow four spaces (two double spaces) between the page header and the main text.
(Also, be sure to put your name and address on the first page, preferably with the word count in the upper right-hand corner.)
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