Here to share with you a little trick, hope to help you: in fact, the method is very simple, find a side with sticky things, such as tape, double-sided tape and so on. Do not use sharp objects, otherwise it will poke the dust into the more inside the gap, unless the dismantling machine is cleaned.
I use double-sided tape, tear the fold in half, and then sweep a circle in the phone speaker, charging interface will become clean. Wipe the metal frame with your hand first, and then wipe it with a clean cloth. Tutorial supplement: Maybe you just don't have tape around you, no double-sided tape, what should you do at this time?