Yes you would give energy to yourself as if working on another person. The process is the same.
I found working in a mirror confusing at times and so just closed my eyes and felt the energy instead. There is nothing wrong with pointing at the mirror or your body directly. The main thing is that you get results. If you have clear intention the energy will follow your direction. It doesn't matter if you are doing sword fingers pointing at the moon and you are trying to open the tail bone, if the intention is clear the energy will just go there and do it's work.
