# yum install openssl
# yum install openssl-devel
# yum install perl
# yum install perl-Net-SSLeay perl-Crypt-SSLeay
# rpm --import http://www.webmin.com/jcameron-key.asc

Create the /etc/yum.repos.d/webmin.repo file containing :

[webmin]
name=Webmin Distribution Neutral
baseurl=http://download.webmin.com/download/yum
enabled=0

Then run:

# yum --enablerepo=webmin install webmin

Check installation success with:

/etc/init.d/webmin status

If everything is good and webmin is running access it via:
https://yourdomain.com:10000/