1. Install and configure the necessary dependencies

On CentOS, the commands below will also open HTTP and SSH access in the system firewall.

sudo apt-get install -y curl openssh-server ca-certificates

If you would like outbound email support, install Postfix or configure an SMTP server.

2. Add the GitLab package server and install the package

curl -sS https://packages.gitlab.com/install/repositories/gitlab/gitlab-ce/script.deb.sh | sudo bash
sudo apt-get install gitlab-ce

If you are not comfortable installing the repository through a piped script, you can find the entire script hereand select and download the package manually and install using

dpkg -i gitlab-ce-XXX.deb

3. Configure and start GitLab

sudo gitlab-ctl reconfigure 

Reconfiguring GitLab will take a couple of minutes, as components are set up and started. A log is displayed of all actions, which will include green and grey lines.

4. Browse to the hostname and login

On your first visit, you’ll be redirected to a password reset screen to provide the password for the initial administrator account. Enter your desired password and you’ll be redirected back to the login screen.

The default account’s username is root. Provide the password you created earlier and login. After login you can change the username if you wish.