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When connecting your battery, connect the positive (red) first and the negative (black) second. When removing the battery, disconnect the negative (black) first and the positive (red) second. Been doing this for nearly 30 years. ALWAYS connect the positive post first.
Here's my battery hooked up to a flashlight bulb to make a simple circuit. I've unwrapped a paperclip to make a piece of connecting wire and I'm holding that between the bottom of the battery and the side of the bulb. If you look closely, you can see the bulb is shining.