If you're just beginning, go slow. The key to making bath bombs is to get exactly the right mix of dry ingredients and wet. Too dry and your bombs will crumble and fall apart. Too wet and they will fizz and warp and swell and morph.
- With whisk in hand, squirt a few drops of the liquid into the center of the dry ingredients. It will immediately start to fizz. Start mixing right away with the whisk - this stops the fizzing by incorporating the liquid into the rest of the dry ingredients.
- Keep adding the liquid slowly, stirring continually, until it's all been added to the bowl. You'll notice the mix has thickened a bit, gotten heavier.