Goto the homepage, and download it.... you may find a binary, or you may have to compile from source.
if you have a binary, it will probably be in rpm form, to install rpm
'rpm -Uvh /path/to/rpm/package_name.rpm'
if you get dependency failures, then seach your install cd's or http://rpmfind.net
for the package u need.
OR, if you have source code, make sure you have development tools installed.
your compiler.... and rpobably X-development stuff.
tar -zxf /path/to/the/archive to decompress .tar.gz or .tgz files
tar -jxf /path/to/the/archive to decompress .tar.bz2 files
unzip /path/to/zip to decompress zip files
if any errors pop up dureing the configure stage, resolve them.