Prerequisites

Please note, some of these packages may not be strictly required, but the lists should be sufficient.

Debian / Ubuntu

sudo apt-get update
sudo apt-get install gcc libtool bison pkg-config gettext make bzip2 g++ wget

Fedora / CentOS / RedHat

yum update -y
yum install -y make automake glibc-devel gcc-c++ gcc bison pkgconfig gettext-libs autoconf libtool wget

Installation

Download the sources for the latest version of Mono

wget http://download.mono-project.com/sources/mono/mono-2.10.8.tar.bz2

Unpack the archive

tar xjf mono-2.10.8.tar.bz2
cd mono-2.10.8

Configure the build process

./configure --prefix=/opt/mono --with-sgen=yes --with-sgen
(If you do not wish to install mono into a separate folder, replace /opt/mono with /usr/local)

Build the sources

make

Install mono to target directory

This part takes a while...

sudo make install

Mono should now be installed in /opt/mono directory. Add /opt/mono/bin to your $PATH, and /opt/mono/lib to your $LD_LIBRARY_PATH.

Check installation

mono --version