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Before cleaning your belly button, take a quick shower. This will help loosen up any dirt or lint in your belly button. You don't need to do anything special in the shower. Just shower as you normally would using regular soap and water. It's best to clean out your belly button using a salt solution. Mix a teaspoon of table salt into a cup of water. Mix the salt in until it dissolves. You can use your fingers or a small rag to clean your belly button. If you use your fingers, wash your hands first. Dip your rag or fingers into the salt solution. Gently massage the inside of your belly button. This will loosen up any lint or other dirt and debris. If some pieces of lint are very large, you may have to pull them out of your belly button. Do this using plain water. Gently pat dry the area around your belly button dry with a clean rag. Belly button infections can happen due to poor hygiene or a recent piercing. You should see a doctor as soon as you can in the event of an infection. Signs of a belly button infection include: Red or itchy skin near the belly button Swelling A bad smell Discharge from the belly button Pain or blistering around the belly button

Summary:
Take a shower. Make a salt solution. Massage your belly button with the solution. Rinse and dry your belly button when you're done. Consult a doctor if you have a belly button infection.