Question: how to create jcl in mainframe?
Answer: Allocate a data set to contain your JCL. Use ISPF (or equivalent function) to allocate a data set named. ... 
Edit the JCL data set and add the necessary JCL. ... 
Submit the JCL to the system as a job. ... 
View and understand the output from the job. ... 
Make changes to your JCL. ... 
View and understand your final output.