Before you print tags with Dot Matrix Shellstock Tags, you will need to designate a tag printer and set up the driver to print them properly.  To do this, start Shellstock Tags and click the Setup button in the Configuration section in the lower right of the main screen.  In the Setup screen that opens, click the 'Printer' tab. 

Select the printer you will use to print tags and leave all the other settings as is -- you can come back and change those later if you need to.  Click 'Save Changes' and 'Quit Setup' at the bottom of the Setup screen, and print some test tags on regular paper.

You might need to repeat this these steps if you change printers or printer drivers.

Place your sheet of test tags over a sheet of your tag stock, and hold up to window or even light source so you can see if the data fields are printing in the right spaces.  If they're not, go into your printer driver's properties or preferences, and make sure the paper source is set to 'Tractor Feed' or 'Continuous'.  Also see these solutions for more tips on fine tuning your tag printing: Dot Matrix Printing Help