If you have configured your server according to the example Configuring the puppet master (server), you can use the same puppet.conf on your client nodes. Simply copy /etc/puppet/puppet.conf from your server to any client nodes.
Otherwise, after installing Puppet, edit the default /etc/puppet/puppet.conf that was created during the install process, or use this example puppet.conf.
The only part you should have to change is the hostname at the top:
server = hostname.test.com
Substitute your server’s hostname here. Note that this parameter is optional for the server, but if you configure it here, you can use the same puppet.conf on the clients and on the server.