When using SSH URIs with GIT it in turn relies on accessing your own private SSH key to talk to the git server.
To make this work seamlessly without any additional commands things like "git clone" etc.
Create Directories
Log into the server using your own user id and cd into your home directory:
cd ~
Then create the ".ssh" directory:
mkdir -p ~/.ssh && chmod 700 ~/.ssh
Upload File
Now, using an SFTP, client on your desktop log into the server and upload your private key file from your local machine into the newly created .ssh directory.
After uploading the file, make sure it is named "id_rsa" and inside the ".ssh/" directory.
Adjust Permissions
Once the file is uploaded, go back in to your SSH command line session and adjust the permissions by running this command:
chmod 600 ~/.ssh/id_rsa
Run Your Git Commands
With this file in place you should now be able to run your GIT commands as long as that key's public string has been added to the GIT server.
For example this would create a new directory for your project then do a git clone of it from GIT Hub:
mkdir mynewproject
cd mynewproject
git clone git@github.com:yourcompany/yourrepo.git .