If you are not familiar with YAML, CSS, and some global options of RMarkdown formating, you can using the following steps to layout your assignments.

1. Open a new RMarkdown file 
2. Choose "Document" and check HTML as the Default Output Format
3. Delete EVERYTHING in the window to make a blank document
4. Copy the following three blocks of code and paste them into the blank document
5. Save it into your designate location (folder)
6. Adjust the first three lines of YAML header: title, author, and date 
============================ The following are three blocks of code  to be copied ===================

---
title: "An RMarkdown Template for Statistical Reports"
author: "Your Name "
date: "Date"
output:
  pdf_document: 
    toc: yes
    toc_depth: 4
    fig_caption: yes
    number_sections: yes
  word_document: 
    toc: yes
    toc_depth: 4
    fig_caption: yes
    keep_md: yes
  html_document: 
    toc: yes
    toc_depth: 4
    toc_float: yes
    fig_width: 6
    fig_caption: yes
    number_sections: yes
    theme: readable
editor_options: 
  chunk_output_type: console
---

```{=html}

<style type="text/css">

/* Cascading Style Sheets (CSS) is a stylesheet language used to describe the presentation of a document written in HTML or XML. it is a simple mechanism for adding style (e.g., fonts, colors, spacing) to Web documents. */

h1.title {  /* Title - font specifications of the report title */
  font-size: 24px;
  color: DarkRed;
  text-align: center;
  font-family: "Gill Sans", sans-serif;
}
h4.author { /* Header 4 - font specifications for authors  */
  font-size: 20px;
  font-family: system-ui;
  color: DarkRed;
  text-align: center;
}
h4.date { /* Header 4 - font specifications for the date  */
  font-size: 18px;
  font-family: system-ui;
  color: DarkBlue;
  text-align: center;
}
h1 { /* Header 1 - font specifications for level 1 section title  */
    font-size: 22px;
    font-family: "Times New Roman", Times, serif;
    color: navy;
    text-align: center;
}
h2 { /* Header 2 - font specifications for level 2 section title */
    font-size: 20px;
    font-family: "Times New Roman", Times, serif;
    color: navy;
    text-align: left;
}

h3 { /* Header 3 - font specifications of level 3 section title  */
    font-size: 18px;
    font-family: "Times New Roman", Times, serif;
    color: navy;
    text-align: left;
}

h4 { /* Header 4 - font specifications of level 4 section title  */
    font-size: 18px;
    font-family: "Times New Roman", Times, serif;
    color: darkred;
    text-align: left;
}

body { background-color:white; }

.highlightme { background-color:yellow; }

p { background-color:white; }

</style>
```
```{r setup, include=FALSE}
# Detect, install, and load packages if needed.
if (!require("knitr")) {
   install.packages("knitr")
   library(knitr)
}
if (!require("leaflet")) {
   install.packages("leaflet")
   library(leaflet)
}
if (!require("EnvStats")) {
   install.packages("EnvStats")
   library(EnvStats)
}
if (!require("MASS")) {
   install.packages("MASS")
   library(MASS)
}
if (!require("phytools")) {
   install.packages("phytools")
   library(phytools)
}
#
# Specifications of outputs of code in code chunks
knitr::opts_chunk$set(echo = FALSE,  # include code chunk in the output file
                   warning = FALSE,  # Sometimes, your code may produce a warning
                                     # messages, you can choose to include the
                                     # warning messages in the output file. 
                   message = FALSE,  
                   results = TRUE,   # you can also decide whether to include 
                                     # the output in the output file.
                   comment = FALSE   # Suppress hash-tags in the output results.
                      )   
```