Adding a signed certificate from a signing authority

Apologies I seem to be hogging this today. My radius server is working fine, so now I want to add a signed certificate from a certificate authority. Are there any pointers on how to do this. I have found and carried out the steps on the wiki site around using snake oil certificates and then

Re: Adding a signed certificate from a signing authority

Hi, I have found and carried out the steps on the wiki site around using “snake oil” certificates and then creating your own producution certificates. But I now would like to add the externally signed certificate for added security. surejust put the relevant files into the right