Connect the iPhone to your computer with a USB cable
Open Finder on Mac or iTunes on Windows or older Mac
Select your iPhone when it appears
Choose the content you want to sync
Click Apply or Sync
Wait for the sync to finish
Disconnect the iPhone safely
To sync wirelessly, connect iPhone and computer to the same Wi-Fi network
Enable Wi-Fi syncing in Finder or iTunes
Click Sync to start wireless syncing
To sync with iCloud, go to Settings on iPhone
Tap your name
Tap iCloud
Turn on the items you want to sync
Make sure you are signed in with the same Apple ID on all devices