my iphone

Step 1: Prepare your iPhone for restoration
Click the iTunes menu located on the left side of the main iTunes toolbar, select Check for Updates from the resulting drop-down menu and ensure you have the latest version of iTunes. If not, download and install the latest version thereof. Afterward, connect your iPhone to your computer via USB and click the gray Back Up Now button when viewing the Summary tab for your given device in iTunes. Alternatively, follow our guide on how to use iCloud to back up the device you Apple’s remote servers. Although backing up your device is not necessary, doing so will store your photos, apps, contacts, settings, and other data so you can automatically restore other iOS devices from the backup down the line.
Step 2: Restore your iPhone
Once the backup is complete, click the gray Restore iPhone button when viewing the Summary tab for your given device in iTunes. Click the Restore button in the resulting pop-up window to confirm your decision, and if prompted, click the Agree button to agree to the software license agreement and begin downloading the necessary iOS software file before restoring.
Step 3: Ensure the phone was restored
 Once the restoration process is complete — a process that may take up to several minutes — check to ensure the phone has been restored to the original factory settings. If done correctly, you’ll once again be presented with the iOS Setup Assistant upon startup, from which you can then restore your phone from backup or continue the process as if setting up a new phone entirely. It’s like it just came off the assembly line at Foxconn all over again.