On any functioning iPhone, the SIM tray is below the Lock button on the right edge of the phone; it resembles a thin, oval cut-out with a hole in it. If you're attempting to remove an iPad's SIM card, you'll usually find the SIM tray at the bottom of the right edge of the tablet, though the iPad 3 and 4 have the SIM tray near the top-left corner. Insert a bent paperclip, a needle, or a similarly thin object into the hole near the bottom of the SIM tray and gently push until the tray pops out. You can gently lift out the card from the tray, or you can turn the tray over and allow the card to fall onto a soft surface (e.g., a towel). Make sure that you don't touch the gold connectors on the bottom of the SIM card. The SIM card should only fit one way into the tray: the angled edge should be in the top-right corner of the tray. It should click back into place, at which point the back of the SIM tray should be flush with the body of the phone. Press the Lock button to do so. After your iPhone finishes restarting, you may be prompted to enter your Apple ID password. If you set a SIM PIN for your phone, you'll have to enter it before you can use your phone on your carrier's network.

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Write a summary of the previous text in Vietnamese:
Tìm khay SIM. Lấy khay SIM ra. Lấy thẻ SIM cũ ra khỏi khay. Lắp thẻ SIM mới vào khay. Lắp lại khay SIM vào điện thoại. Mở nguồn iPhone.