Turn off your Apple Watch if desired
Place the watch face down on a clean, soft surface
Locate the band release button on the back of the watch
Press and hold the band release button
Slide the band piece sideways out of the slot
Repeat for the other band piece
Align the new band piece with the slot
Slide it in until you feel or hear a click
Repeat for the second piece
Gently tug each band piece to confirm it is secure