Adding Kali Linux Repositories

Having trouble to install the latest updates using repositories and to add repositories to source file.

Solution 

Open a terminal and follow these instructions:

1. Type sudo -i
2. Type in your password.
3. Type touch /etc/apt/sources.list
4. Type chmod 644 /etc/apt/sources.list
5. Type echo "deb http://http.kali.org/kali kali-rolling main contrib non-free" > /etc/apt/sources.list
6. Type apt-key adv --keyserver hkp://keys.gnupg.net --recv-keys 7D8D0BF6
7. Type apt-get update
8. Now install whatever it is that you want to install.