Manual installation (not recommended)

WARNING: This method is not recommended and not officially supported, since you should use the installer instead. Use this method if the installer isn't an option and you can already deal with PostgreSQL, puma or passenger, NGNIX and SSL (with letsencrypt, for instance).
This guide assumes you've already installed all the necessary packages on your system.
The created directory structure herein is to be used with capistrano.

Folder structure

First, create the main folder, clone the repo to a repo directory, and create the needed folders:
mkdir consul
cd consul
git clone --mirror repo
mkdir releases shared
mkdir shared/log shared/tmp shared/config shared/public shared/storage
mkdir -p shared/public/assets shared/public/system shared/public/ckeditor_assets shared/public/machine_learning/data

Initial release

Extract from the repo the first release to the respective directory, and create the symbolic link of the current release (replace <latest_consul_stable_version> with the latest version number, like 1.3.1 or 1.4.1):
cd repo
git archive <latest_consul_stable_version> | tar -x -f - -C ../releases/first
cd ..
ln -s releases/first current

Gems installation

Install the gems CONSUL depends on:
cd releases/first
bundle install --path ../../shared/bundle --without development test
cd ../..

Configuration files

Generate the database.yml and secrets.yml files:
cp current/config/secrets.yml.example shared/config/secrets.yml
cp current/config/database.yml.example shared/config/database.yml
cd releases/first/config
ln -s ../../../shared/config/database.yml
ln -s ../../../shared/config/secrets.yml
cd ../../..
Edit the shared/config/database.yml file, filling in username and password with the data generated during the PostgreSQL setup.
We now need to generate a secret key:
cd current
bin/rake secret RAILS_ENV=production
cd ..
Copy that generated key, and edit the shared/config/secrets.yml file; under the section production, change the following data:
secret_key_base: enter_the_secret_key_you_have_just_generated
server_name: enter_your_domain
If you aren't using a SSL certificate, replace the line saying force_ssl: true with force_ssl: false.

Database setup

Create a database, load the seeds and compile the assets:
cd current
bin/rake db:migrate RAILS_ENV=production
bin/rake db:seed RAILS_ENV=production
bin/rake assets:precompile RAILS_ENV=production

Starting the application

And, finally, start the Rails server:
bin/rails s -e production
Congratulations! Your server is now running in the production environment