Go to ISPF on the IBM MAinframe.
Go to the EDIT screen and bring up some source code.
Once there, on the COMMAND Line type in 'SET TRACE ON'
This sounds too obvious... you are editing the program and you issue a command that enables tracing... you will still need to:
1. save the modified source
2. re-compile and
3. linkedit before
4. executing the program.
It is not clear that you did all of those things.
I think SET TRACE ON is an editor macro that is local to your site. Such editor macros are just a easier way to add stuff to your program that you could have added manually. Your program will be modified from the original source. My suggestion is to save a copy of the source, issue SET TRACE ON, then compare with the copy. In this way, you will be able to determine what changes were made by the macro and it will help you to learn how the tracing is performed. You may wish to add your own trace lines for some particular situation.
What would you say to this 'person" that replied:
Well, Beets-kun ?
The Japanese language uses a broad array of honorific suffixes for addressing or referring to people. See https://en.wikipedia.org/wiki/Japanese_honorifics
It was not intended to be derogatory.