Set up GIT on Linux

First: Download and Install GIT
At the heart of GitHub is an open source version control system (VCS) called Git*. Created by the same dudes that created Linux, Git is responsible for everything GitHub related that happens locally on your computer.
i) Download and install the latest version of Git with Synaptic.
   We suggest you install git-core, git-gui, and git-doc.

When you’ve selected git-core, git-gui, and git-doc, hit “Apply” to install them.

If you don’t have a package manager like Synaptic, or you’d rather install the necessary git components from the command line, you can alternatively run the script below:
$ sudo apt-get install git-core git-gui git-doc

Next: Set Up SSH Keys

We use SSH keys to establish a secure connection between your computer and GitHub. Setting them up is fairly easy, but does involve a number of steps.

To make sure you generate a brand new key, you need to check if one already exists. First, you need to open an app called Terminal.

i) Check for SSH keys. Have an existing key pair? You can skip to Step 4.

First, we need to check for existing ssh keys on your computer:

$ cd ~/.ssh

If it says “No such file or directory“ skip to step 3. Otherwise continue to step 2.

ii) Backup and remove existing SSH keys.

Since there is already an SSH directory you’ll want to back the old one up and remove it:  

$ lsLists all the subdirectories in the current directoryconfig id_rsa id_rsa.pub known_hosts$ mkdir key_backupmakes a subdirectory called "key_backup" in the current directory$ cp id_rsa* key_backupCopies the contents of the id_rsa directory into key_backup

$ rm id_rsa*

iii) Generate a new SSH key.

To generate a new SSH key, enter the code below. We want the default settings so when asked to enter a file in which to save the key, just press enter.

$ ssh-keygen -t rsa -C "your_email@youremail.com"Creates a new ssh key using the provided emailGenerating public/private rsa key pair.

Enter file in which to save the key (/Users/your_user_directory/.ssh/id_rsa):<press enter>

Press enter until you get this screen  - 

Your identification has been saved in /Users/your_user_directory/.ssh/id_rsa.Your public key has been saved in /Users/your_user_directory/.ssh/id_rsa.pub.The key fingerprint is:01:0f:f4:3b:ca:85:d6:17:a1:7d:f0:68:9d:f0:a2:db user_name@username.comThe key's randomart image is:+--[ RSA 2048]----+|     .+   +      ||       = o O .   ||        = * *    ||       o = +     ||      o S .      ||     o o =       ||      o . E      ||                 ||                 |

+-----------------+

iv) Add your SSH key to GitHub.

On the GitHub site Click “Account Settings” > Click “SSH Public Keys” > Click “Add another public key”

Open the id_rsa.pub file with a text editor (Notepad, TextEdit, or gedit will do just fine). This is your public SSH key. You may need turn on “view hidden files” to find it because the .ssh directory is hidden. It’s important you copy your SSH key exactly as it is written without adding any newlines or whitespace.Now paste it into the “Key” field.

Now paste it into the “Key” field.

Hit “Add Key.”

v) Test everything out.

To make sure everything is working you’ll now SSH to GitHub. Don’t change the “git@github.com” part.That’s supposed to be there.

$ ssh git@github.com

Which should give you this:

The authenticity of host 'github.com (207.97.227.239)' can't be established.RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48. Are you sure you want to continue connecting (yes/no)?

PTY allocation request failed on channel 0 Hi username! You've successfully authenticated, but GitHub does not provide shell access. Connection to github.com closed.

Then: Set Up Your Info

i) Set your username and email.

Git tracks who makes each commit by checking the user’s name and email. In addition, we use this info to associate your commits with your GitHub account. To set these, enter the code below, replacing the name and email with your own. The name should be your actual name, not your GitHub username.

$ git config --global user.name "Firstname Lastname"

$ git config --global user.email "your_email@youremail.com"

ii) Set your GitHub token.

Some tools connect to GitHub without SSH. To use these tools properly you need to find and configure your API Token.

On the GitHub site Click “Account Settings” > Click “Account Admin.”

At the command line run the following code, using your GitHub username and token in place of the ones show

$ git config --global github.user username

$ git config --global github.token 0123456789yourf0123456789

*Note* If you ever change your GitHub password, a new token will be created and will need to be updated.