This video from Utah State University Extension is a great resource. You can tell by the way this video flows that he is used to educating folks on how to prune roses. The whole video walks you completely through pruning one rose bush.
The guy in the video evidently loves to prune. What’s cool is he knows what he is talking about. His main approach to pruning a rose is to know what you want to keep. Then, it’s easy to determine what you don’t want and will prune.
Prune in the early springs as the rose start to bud out. This will help you see which canes are healthy and strong. He suggests keeping 4-6 canes about size of your finger and about 18-24 inches tall. Prune canes in the middle, but keep the canes growing on the outside if healthy. Really, you need to watch this guy prune a rose bush. He makes it a very simple process.
The video is a little lengthy at just over 4 minutes. But, it’s a great educational video from an extension agency on how to prune roses. And, he’s just not talking about it. He’s doing it. So, you can actually SEE how to prune a rose. Just watch it! It’s worth your time.