You need two nodes for Puppet to work, one Puppet master and one is Puppet agent. IIn this case there will be one puppet master and one puppet agent.
Create a CentOS node which will act as the master
Look at available timezones
timedatectl list-timezones
Select the one that suits you
sudo timedatectl set-timezone America/New_York
Install NTP
sudo yum -y install ntp
sudo ntpdate pool.ntp.org
Start NTP
sudo systemctl restart ntpd
sudo systemctl enable ntpd
Install Puppet Server
sudo rpm -ivh https://yum.puppetlabs.com/puppetlabs-release-pc1-el-7.noarch.rpm
sudo yum -y install puppetserver
Configure memory allocations. Go to this file and chnage the JAVA_ARGS
sudo vi /etc/sysconfig/puppetserver
JAVA_ARGS="-Xms3g -Xmx3g"
Start Puppet Server
sudo systemctl start puppetserver
sudo systemctl enable puppetserver
Install Puppet Agent
sudo systemctl enable puppetserver
sudo yum -y install puppet-agent
sudo /opt/puppetlabs/bin/puppet resource service puppet ensure=running enable=true
Sign Certificate
List all the certificates
sudo /opt/puppetlabs/bin/puppet cert list
Sign them
sudo /opt/puppetlabs/bin/puppet cert sign certificate_name
or sign all of them
sudo /opt/puppetlabs/bin/puppet cert sign --all
And you're done:)