A new computer can be added to the Puppet management of a server with a few steps:

1. On the server, the new computer has to be added as a new node.
2. On the agent, the following lines have to be added to the file /etc/puppet/puppet.conf:

   [main]
   certname=<hostname>
   
   [agent]
   server=<puppet server>

3. On the agent, run

   puppet agent --test

4. On the server, list and sign the newly created SSL certificate:

   puppet cert list
   puppet cert sign <hostname>