R.T.F.M. ...

In the submission guidelines for magazines I often see the following advice:
Use standard manuscript format.

The guidelines then go on to describe aspects of the standard, which differ from one magazine to another, especially for electronic submissions.

1. Use 12 point font, or 10 point, or 12 or 10 point.

2. Single space after a period. Or not.

3. Name and page number in the header, or story title and page number, or name and story title and page number, or nothing at all.

My favorite is a magazine that refers to the SF Writers of America site for reference. The site has three different articles on manuscript format. And the magazine that references it has guidlines that depart from all three.

So, Read The Fine Manuscript guidelines.

Or perhaps you have a 'standard' understanding of RTFM.