Here are some tips to consider while cleaning iPhone charging port :-
1. Never start the cleaning process with the device turned on.
2. Don't put pressure on the inner walls with a toothpick or any hard object, as it may damage the micro-electronic pins present there.
3. Try to avoid placing cotton on the edge of the toothpick, as it may push the debris deeper.
4. Never use a wet cloth, toothbrush, or cotton to clean the debris, as it may cause a short circuit to the device.