1. Safety first: Always wear personal protective equipment when working with granite cobbles. This includes safety goggles, earplugs, work gloves, and a dust mask.

2. Choose the right tool: To split granite cobbles, a chisel and hammer can be used, but it's best to use a more powerful tool such as a hydraulic splitter. A hydraulic splitter can apply a precise and consistent amount of pressure to the granite cobbles.

3. Mark where to split: Use a chalk or pencil to mark where you want to split the granite cobbles. This ensures that the split will be accurate and precise.

4. Apply pressure gradually: Start with a low pressure setting and gradually increase it until the granite cobbles split. This helps to avoid any sudden and unpredictable fractures.

5. Use a wedge: If you're using a chisel and hammer, place a wedge into the chalk line and hammer it in. This will create a split in the granite cobble.

6. Clean up: After you've finished splitting the granite cobbles, make sure to clean up any debris or dust. This will ensure the area is safe and avoid any potential accidents.