Anyone grinding a straight edge knows that it can be frustrating to get a good 'edge' because the marker line tends to fool the eye. You can check your work by flipping the piece upside down. If you need to 'straighten' your glass piece out more, it will instantly be visible. 

  Another 'must have' tool is the corkbacked ruler. If you use one of these when cutting all of your straight cuts, you should eliminate the problem above.  I advise my students to avoid too many straight cuts in their early projects because a straight cut that is wrong is glaringly apparent on a finished piece. Instead, focus on more natural projects. Then, if you make an error, the eye doesn't really see it...it just becomes part of a bigger picture!

 If this guide helped you in any way, I'd appreciate you clicking the 'yes' button at the bottom of the page. :)