- 1). Find a good spot on the shell to drill. This should be thick enough to stand up to the drilling without shattering, but not so thick that it's too tough to drill through. With most shells, a thickness roughly that of most coins is a good place to start, or slightly thicker or thinner than this. Avoid areas that are closer to the thickness of tag board or thicker than most metal spoons.
- 2). Mark the spot on the shell using a pencil. Make either a dot or an "x" or mark the spot (use an "x" if the shell is bumpy, as the tool may slip over the surface).
- 3). Press the shell into some soft clay with the spot you've just marked facing upward; this will secure the shell while you cut the hole, keeping your hands safe.
- 4). Fit an oscillating power tool with a standard engraving bit; this is the type with a tiny, ball tip that looks like a series of tiny oscillating blades.
- 5). Turn on the tool. Set the speed dial to a middle setting.
- 6). Cut the hole. Hold the tool so the tip is pointing towards the shell straight-on (i.e., not at an angle). Press the tip gently against the shell as it starts to penetrate and cut the hole. Avoid pressing too hard, as this may damage the tip.
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