Ten Simple Rules for Getting Published states:
Rule 7: Start writing the paper the day you have the idea of what questions to pursue.
This sounds like very good advice, not just because you would pace out the act of writing your paper over the entire duration of your research, but it would also help you stay focused and keep track of your progress.
However, in practice, how is this possible? To start writing a paper, I must first know what format and style it should be written in. To know that, I would consult the guidelines of the journal in which I want publish. But the choice of journal depends on the quality of the research and notability of findings. But if I start writing on the day that I start my research, how can I know what journal the research will be good enough for?
For instance, if I shoot high and assume I am going to have a Nature paper, what do I do if a year down the line, it turns out that I was unable to succeed in reaching my goals and Nature would not possibly accept my research? Now I have to rewrite from scratch for another journal, and the time I spent slowly building up my Nature manuscript is wasted. I might as well have focused on research only at first, and left the writing part for last.
What journal's submission guidelines do I pick to follow this Rule 7? The most prestigious journal? The humblest journal? Some generic set of guidelines for "no journal"?
Rule 9 from the same text says:
Rule 9: Decide early on where to try to publish your paper.
But how can you know ahead of time where you will be able to publish, especially if you don't have much experience publishing?