Added comments to code, and added index to each section

install youtube-dl in android.md

@@ -4,35 +4,52 @@ Tutorial to fast install [youtube-dl](https://github.com/ytdl-org/youtube-dl/) i
 
 *Based on https://www.reddit.com/r/Piracy/comments/baufql/youtubedl_the_easy_way_on_android/*
 
-# Quick Install
+1. [Install and configure youtube-dl](#Install-and-configure-youtube-dl)
+2. [Extras](#Extras)
+3. [All-In-One](#All-In-One)
 
-## Install Termux
+# Install Termux
 https://termux.com/
 
-## Open Termux and run this:
+# Open Termux and run this:
 
-### Install and configure youtube-dl
+## Install and configure youtube-dl
 
+```bash
+    # Ask for storage permission
     termux-setup-storage &&
+    # Install youtube-dl
     apt update && apt upgrade && apt install python ffmpeg && pip install youtube-dl &&
+    # Configure to download videos in `Downloads/{URL's provider (e.g. Youtube)}/{uploader}/{filename}`
     mkdir -p ~/.config/youtube-dl &&
     echo "# Default Output Directory and Pattern
     -o /data/data/com.termux/files/home/storage/downloads/%(extractor_key)s/%(uploader)s/%(title)s-%(id)s.%(ext)s" > ~/.config/youtube-dl/config &&
+    # Configure to open shared URLs with `youtube-dl {url}`
     mkdir ~/bin &&
     echo "#!/bin/bash
     url=$1
     youtube-dl $url" > ~/bin/termux-url-opener &&
     chmod +x ~/bin/termux-url-opener
+```
 
-### Extras (install nano, and add special keys to keyboard)
+## Extras
+
+```bash
+    # Add special keys to keyboard
     mkdir ~/.termux
     echo "extra-keys = [ \
         ['ESC', '/', '|', 'HOME', 'UP', 'END', 'PGUP', '-'], \
         ['TAB','CTRL', 'ALT', 'LEFT', 'DOWN', 'RIGHT', 'PGDN', '~'] \
     ]" > ~/.termux/termux.properties
+    # Install nano
     apt install nano
+```
 
-### All-In-One (youtube-dl + extras)
+## All-In-One
+
+youtube-dl + extras
+
+```bash
     termux-setup-storage &&
     apt update && apt upgrade && apt install nano python ffmpeg && pip install youtube-dl &&
     mkdir -p ~/.config/youtube-dl &&
@@ -47,4 +64,5 @@ https://termux.com/
     echo "extra-keys = [ \
         ['ESC', '/', '|', 'HOME', 'UP', 'END', 'PGUP', '-'], \
         ['TAB','CTRL', 'ALT', 'LEFT', 'DOWN', 'RIGHT', 'PGDN', '~'] \
-    ]" > ~/.termux/termux.properties
+    ]" > ~/.termux/termux.properties
+```