add commmands and directory explanations

Author: SDSTony

README.md

@@ -2,12 +2,41 @@
 
 
 
+## Repository template
+
+Below are the folders and files in `book` directory:
+
+- `_build` : built files using `jupyter-book build`
+
+- `chapters ` : .ipynb files of the contents
+
+- `pics` : image files used on the contents
+- `_config.yml` : configuration file for Jupyter Book
+- `_toc.yml` : table of contents file for Jupyter Book
+
+
+
 ## How to contribute
 
 1. fork [Pseudo-Lab/Tutorial-Book](https://github.com/Pseudo-Lab/Tutorial-Book)
+
 2. clone the forked repo to your local computer
+
+   ```bash
+   git clone
+   ```
+
 3. make necessary changes on the local repo
+
 4. push the changes made on the local repo to the forked repo
+
+   ```
+   git add
+   git commit
+   git push
+   ```
+
 5. create a pull request from the forked repo to [Pseudo-Lab/Tutorial-Book](https://github.com/Pseudo-Lab/Tutorial-Book)
+
 6. Repeat step 3 and 5