The people at Puppet Labs have their own repository servers for puppet, which is very easy when it comes down to installing and maintaining the server and agent. Although the EPEL repository also provides puppet packages, they tend to be old or not up to date. Hence, I recommend using the Puppet Labs' yum repositories.
This recipe covers a monolithic install. Perform the following steps:
~]# subscription-manager repos --enable rhel-6-server-optional-rpms
puppetlabsrepository installer, as follows:
~]# curl -Lo /tmp/puppetlabs-release-el-7.noarch.rpm https://yum.puppetlabs.com/puppetlabs-release-el-7.noarch.rpm ...