Instructions for formatting the paper are not explicitly stated in the AMA Manual of Style. Please check with your instructor for guidelines on margins, line spacing, fonts, indents, title page, etc.
Headings: Section 2.8 of the AMA Manual of Style recommends using headings, so the paper is easier to read.
For a research paper: Introduction, Methods, Results, and Discussion.
All other papers: Minimum of 2 headings
Again, please check with your instructor for guidance.