A pre-treat coaster with a gloss finish makes the image stand out after the engraving. 

This file has been pre-prepared for a Slate Coaster, and you should not need to manipulate it in any way. 

Focus on the F1, and make sure you get this right, as an unfocused laser will create a poor image. 

I used the slide extension to frame the image, ensuring that there is a similar gap at each end; it just looks better. 

Then hit go and sit back …