Pry off the back cover.

Take away the battery after power off the phone.

Peel off the warranty label.

There is a screw beneath.

Take away SIM cards and SD card if you have any.

Pry off the back frame with a piece of plastic card.

Install the new speaker.

Power on the phone.

Open the dial pad and dial the samsung test code.

Power off the phone (optional).

Put back the back cover.

Source: Youtube