How to install Redmine

This is the cleanest way I found. If you know any of the steps could be skips, please share :-)

# Ubunut 12.04

# Run the following commands one by one

# install LAMP

tasksel install lamp-server

sudo apt-get install ruby1.9.3 libmysqlclient-dev libapache2-mod-passenger

sudo gem install bundler

# go to the directory where you put the redmine source code
# i.e. replace /path/to/ with your directory path
cd /path/to/redmine

sudo bundle install --without development test postgresql sqlite rmagick

# go into mysql 

# e.g. mysql -u root -p

-- create database
create database redmine character set utf8;

-- create db user
create user 'redmine'@'localhost' identified by 'password.you.want.to.use';

-- assign privileges
grant all privileges on redmine.* to 'redmine'@'localhost';

# create configuration file

cp /path/to/redmine/config/database.yml.example /path/to/redmine/config/database.yml

# put your database details in this file
vi /path/to/redmine/config/database.yml

rake generate_secret_token

sudo RAILS_ENV=production rake db:migrate
sudo RAILS_ENV=production rake redmine:load_default_data

mkdir /path/to/redmine/public/plugin_assets
sudo chown -R www-data:www-data files log tmp public/plugin_assets
sudo chmod -R 755 files log tmp public/plugin_assets

# if email does not work

sudo install postfix
cp /path/to/redmine/config/configuration.yml.example /path/to/redmine/config/configuration.yml
# set email to :sendmail in /path/to/redmine/config/configuration.yml

Reference:
http://www.redmine.org/projects/redmine/wiki/RedmineInstall