Draw the image you wish to etch on a piece of paper. Use a short phrase or a simple image, such as a tree, for example. Use a fine point marker to draw your idea on the polished stone surface. The smooth surface will provide a nice contrast to your etching.
Keep the lines simple for now. Use a ruler to draw straight letters or stylize them free-hand. Draw the outline of a trunk and branches spreading out. Draw in leaves or leave the branches bare, as desired.
Secure the stone in the vise so that it will not move as you etch into it. Put a box beside the vice so that you can use it to brace your arm comfortably as you etch.
Load a pointed diamond drill bit into the tool, and use a medium speed setting to begin carving the lines drawn with the marker. Do not use too much pressure and keep your hand steady. Slowly move the bit along the lines until the outlines are complete.
Load a cone-shaped diamond drill bit, and begin to define the thickness of your lines. Hold the electric tool perpendicular to the marble surface to create a v-shaped trench. Use a flat-top barrel-shaped tip on its side to deepen the cut.
Taper fine lines, such as the tips of branches, with a pointed drill bit. Move the bit in smooth natural curves as you would a pencil or brush.
Add more detail, such as decorative font characteristics or small leaves, to the tree. Use the right drill bits that will give you the shapes you need. Use a round ball-shaped tip and press in lightly to create leaves, or make random texture lines on the trunk with a sharper tip to indicate bark, for example.
Clean the dust from the stone with water and examine the results. Make any final additions or corrections to finish the etching.