Newbie Question about XSD files

[Java Newbie]

Hello -

I am to create a schema file(.xsd) using a list of tag names that is
provided by the user. The application is to be developed in Java. I
have all the tag names in a JTextArea and would like to create a xsd
file with flat catalog of all the elements available. I am not sure
how to start and what the procedure is. Any pointers or guidlines will
be appreciated.

Thanks.