at the top of the program there is source and target selections with a folder next to them. click the folder next to target and navigate to where you want the files to save. then the next time you do a rip, click the drop down and the directory will be available as target.
please read the official guide to answer more questions and if you still need help please post.
you can also set the default output directory for the logï¼Œ ISO and temp files in settings/ general tab