Update wording and fix layout style guide issues

As per markdown style guide, now uses lazy numbering, dashes for
unordered lists and 3-space indents when nested in an ordered list.

Author: MaoShizhong

Diff for: README.md

@@ -11,16 +11,16 @@ If you have suggestions to improve an exercise, ideas for a new exercise, or not
 ## How To Use These Exercises
 
 1. Fork and clone this repository. To learn how to fork a repository, see the GitHub documentation on how to [fork a repo](https://docs.github.com/en/get-started/quickstart/fork-a-repo).
-    * Copies of repositories on your machine are called clones. If you need help cloning to your local environment, you can learn how from the GitHub documentation on [cloning a repository](https://docs.github.com/en/github/creating-cloning-and-archiving-repositories/cloning-a-repository-from-github/cloning-a-repository).
-2. Go to an exercise directory and open the HTML file in a web browser. You can open the file directly or use something like VSCode's Live Server extension.
-3. For each exercise, read the README thoroughly before starting any work.
-    * Each README has a "Self Check" list. Use this to ensure you haven't missed any important details in your implementation.
-4. Make your edits in the `index.html` and/or the `style.css` files in order to make the output in your browser look like the Desired Outcome image(s).
-    * Depending on the instructions of the exercise, you may only need to make edits in one of these files.
-5. Once you successfully finish an exercise, check TOP's solution to compare it with yours.
-   * You should not be checking the solution for an exercise until you finish it!
-   * If your solution differs wildly from TOP's solution (and still passes the self-check criteria), that's completely fine. Do feel free to ask about it in the chatroom if there are parts you do not understand.
-6. Do not submit your solutions to this repo, as any PRs that do so will be closed without merging.
+    - Copies of repositories on your machine are called clones. If you need help cloning to your local environment, you can learn how from the GitHub documentation on [cloning a repository](https://docs.github.com/en/github/creating-cloning-and-archiving-repositories/cloning-a-repository-from-github/cloning-a-repository).
+1. Go to an exercise directory and open the HTML file in a web browser. You can open the file directly or use something like VSCode's Live Server extension.
+1. For each exercise, read the README thoroughly before starting any work.
+    - Each README has a "Self Check" list. Use this to ensure you haven't missed any important details in your implementation.
+1. Make your edits in the `index.html` and/or the `style.css` files in order to make the output in your browser look like the Desired Outcome image(s).
+    - Depending on the instructions of the exercise, you may only need to make edits in one of these files.
+1. Once you successfully finish an exercise, check TOP's solution to compare it with yours.
+    - You should not be checking the solution for an exercise until you finish it!
+    - If your solution differs wildly from TOP's solution (and still passes the exercise's requirements), that's completely fine. Do feel free to ask about it in our Discord if there are parts you do not understand.
+1. Do not submit your solutions to this repo, as any PRs that do so will be closed without merging.
 
 ## Some Hints
 - The official solutions put all changes at the _end_ of the CSS file, which may duplicate some selectors (e.g. there might be a `body {}` in the given CSS and another `body {}` in the solution). When you are working on an exercise, it is best practice to add your CSS to existing selectors instead of duplicating them at the end of the file. We're sacrificing this best practice in our official solutions to make it extra clear to you what things we changed to solve the exercise.