The best way to install Jekyll is via RubyGems:

sudo gem install jekyll

Note that gems will now be avaliable through RubyForge.

If the above command did not work you could try:

sudo gem install mojombo-jekyll -s https://gems.github.com -s https://gems.rubyforge.org

or

sudo gem install mojombo-jekyll --source https://gems.github.com --source https://gems.rubyforge.org

Jekyll requires the gems directory_watcher, liquid, open4, maruku and classifier. These are automatically installed by the gem install command.

If you encounter errors during gem installation, you may need to install the header files for compiling extension modules for ruby 1.8. This can be done on Debian systems by:

sudo apt-get install ruby1.8-dev

On NearlyFreeSpeech you need:

RB_USER_INSTALL=true gem install jekyll

LaTeX to PNG

Maruku comes with optional support for LaTeX to PNG rendering via blahtex (Version 0.6) which must be in your $PATH along with dvips.

(NOTE: remi’s fork of Maruku does not assume a fixed location for dvips if you need that fixed)

RDiscount

If you prefer to use RDiscount instead of Maruku for markdown, just make sure it’s installed:

sudo gem install rdiscount

And run Jekyll with the following option:

jekyll --rdiscount

Or, in your _config.yml file put the following so you don’t have to specify the flag:

markdown: rdiscount

Pygments

If you want syntax highlighting via the {% highlight %} tag in your posts, you’ll need to install Pygments.

On OSX with MacPorts:
sudo port install python25 py25-pygments

Alternatively on OS X Leopard:
sudo easy_install Pygments

On Archlinux:
sudo pacman -S pygments

On Ubuntu:
sudo apt-get install python-pygments

On Gentoo:
sudo emerge -av dev-python/pygments