Windows
Download the archive with editor and plugins then just unzip the archive to any destination.
Ubuntu
For Ubuntu 9.10 "Karmic Koala" and higher (10.04 "Lucid Lynx", 10.10 "Maverik Meercat", ...) do the following steps in terminal:
Stable version:
$ sudo add-apt-repository ppa:mezomish/juffed
Development version:
$ sudo add-apt-repository ppa:mezomish/juffed-dev
Then just
$ sudo apt-get update
$ sudo apt-get install juffed juffed-plugins
Fedora 14
Development version:
$ cd /etc/yum.repos.d
$ sudo wget -nd "http://download.opensuse.org/repositories/home:/TI_Eugene:/QtDesktop/Fedora_14/home:TI_Eugene:QtDesktop.repo"
$ sudo yum install juffed juffed-plugins
Debian 6.0 "Squeeze"
Development version:
Add the following line to your /etc/apt/sources.list
deb http://download.opensuse.org/repositories/home:/TI_Eugene:/QtDesktop/Debian_6.0/ ./
Add the repository key:
$ wget http://download.opensuse.org/repositories/home:/TI_Eugene:/QtDesktop/Debian_6.0/Release.key
$ cat Release.key | sudo apt-key add -
Install:
$ sudo apt-get update
$ sudo apt-get install juffed juffed-plugins
Gentoo
Arch
OpenSUSE
<to be added>