I found a teacher after I left home. I learned from what they taught me, and others mistakes. I was also taught earth magic at the same time. I believe this is important because both methods combined make it easier to handle different types of magical attacks. The simple methods can be quicker and easier for people to do who don't have the experience and background to do ceremonial magic.
Ceremonial magic is very complex and has to be done correctly.
I did countless exorcisms in the next 12 years. I helped out everyone in the group I was in that had made mistakes. I left the group and for the next 18 years I have been doing exorcisms and removing curses for people. I have found that people who haven't practiced magic are having a lot of problems with this also. I believe that this is because of a shift in the balance between good and evil.