A best practice when starting a paper is to organize it in advance. This includes taking advantage of the templates specific journals often presented on the journal's Author Guides or using standardized guidelines like those from the Equator Guidelines. Below are links to some examples that can be used for organizing and planning your paper. 

Equator Guidelines- The EQUATOR (Enhancing the QUAlity and Transparency Of health Research) Network is an international initiative that seeks to improve the reliability and value of published health research literature by promoting transparent and accurate reporting and wider use of robust reporting guidelines.

PRISMA- PRISMA is an evidence-based minimum set of items for reporting in systematic reviews and meta-analyses. PRISMA primarily focuses on the reporting of reviews evaluating the effects of interventions, but can also be used as a basis for reporting systematic reviews with objectives other than evaluating interventions (e.g. evaluating aetiology, prevalence, diagnosis or prognosis).

Journal Specific Guidelines (this is not a comprehensive list)

International Journal of Medical Students 

Harvard Medical Student Review 

Medical Student Research Journal

BMJ Guidelines 

Nature Formatting Guide