There are much of Git setup guidelines out there, and here is another one. This is very short, hope you will find it simple. (below steps are performed on CentOS)
1. Install Git applications:
$ yum install git git-daemon
2. Create the repository (in current directory):
$ git init
$ cp -R /some/first/code/ ./
$ git add .
$ git commit
3. To make it available from the outside accesses, run the git daemon:
$ git daemon --reuseaddr --base-path=/a/git/repo --export-all --detach
4. Then it can be reached at: git://your.host/
$ git ls-remote git://your.host
also with clone, push,...
I plan to make one (or some) more note which records the steps for integrating Git with Apache, Gitweb, SSL, and LDAP. That would be much more longer than this one...
You should check out some really interesting sources about Git: