how can you get the dirt off the keys on the wireless keyboard???

Use a cleaning agent. A mild alcohol or the like. Disconnect the keyboard and dampening a Q tip, gently rub it on the key pads. Leave a while then reconnect the keyboard.

Cleaning your Apple products:

Read recommendations and guidelines for cleaning your Apple computer, iPad, iPhone, iPod, display, or peripheral device.

The materials used to make Apple products vary; in some cases, each product might have specific cleaning requirements which vary by the part you're cleaning. To get you started, here are some tips that apply to all products:

• Use only a soft, lint-free cloth. Avoid abrasive cloths, towels, paper towels, and similar items that might cause damage.
• Unplug all external power sources, devices, and cables.
• Keep liquids away from the product.
• Don't get moisture into any openings.
• Don't use aerosol sprays, solvents, or abrasives.
• Don't spray cleaners directly onto the item.

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I've been cleaning my keyboards with alcohol and a Q-Tip as seventy one describes, for many years. Never had any damage. The trouble with the recommended steps is the keyboard does not get very clean without alcohol.

What I do is put some alcohol on the Q-tip, then blot it on a piece of paper towel before rubbing they keys.