Turn the screw on the top of the binding post with your finger to adjust the speed of the needle. Loosening the screw will slow the needle down. Tightening the screw will speed up the needle. A faster needle performs well on areas with loose skin. Adjust the contact screw until the sound of the tattoo machine stops rattling and smooths out.
Use an Allen wrench to turn the screw on the bottom of the tattoo machine to drop the guard that blocks the springs.
Use your finger to bend the springs to correct the amount of throw from the tattoo machine. The tighter the spring, the harder the throw will be. The throw determines how hard the needle will punch. The harder a needle punches, the deeper the needle will penetrate into the skin. This ultimately will cause the person getting the tattoo more pain and discomfort. If the throw is too light, the tattoo will fade quicker and become blurry.
Return the guard back to it's original position and tighten the screw with an Allen wrench.