Before trading in your iPhone, there are several things you should do to ensure that your personal information is removed and your device is ready for its new owner. Here are the steps you should follow:

1. Back up your iPhone: The first step is to back up your iPhone to iCloud or a computer. This will ensure that your data is saved and can be transferred to your new device.

2. Transfer your data to your new iPhone: If you have a new iPhone, transfer your data to it before trading in your old device.

3. Remove your personal information: Go to Settings > General > Transfer or Reset .

4. Deregister iMessage: If youre switching to a non-Apple phone, deregister iMessage.

5. Remove your SIM card: If youre not trading in your SIM card with your iPhone, remove it.

6. Remove your iPhone from your list of trusted devices: Go to appleid.apple.com and sign in with your Apple ID. Click on "Devices" and remove your iPhone from the list of trusted devices.

7. Cancel your AppleCare plan: If you purchased an AppleCare plan for your device, cancel it.

8. Clean your iPhone: Use a soft dry cloth to wipe the front and back of the device. Carefully clean the speaker grills, earpiece, and other such places too. Be careful not to use any sharp metal pin.

9. Take photos of the phone for your records: This is not a necessary step, but it can be helpful to take photos of your iPhone before trading it in, just in case.

By following these steps, you can ensure that your personal information is removed from your iPhone and that it is ready for its new owner.