What you can do for printing is to either change the color of the grid lines (minor and major) and the thickness. The default color for both types is black and the minor grid lines have a width of 1 while the major ones (every 10) have a width of 5.
If you change the width, it will be more "bold" but you have to be careful and not make it so wide as to obscure the stitch symbols.
Look under "Options" and "Printing". You need Grid Line Printing options.