[header] How to cut slate [title] Flip the slate over when manually cutting the slate. [step] It's much easier to draw and cut a straight line across the bottom side of the slate. When cutting slate manually with a hammer and chisel or a handheld slate cutter, flip it over and cut along the flat underside of the tiles. 
[title] Mark and cut the top of the slate when using power tools. [step] When using power tools, it's more important that the slate lies flat on the surface you're cutting on.