Gently pull the LCD screen upwards.

It can be tricky do this, you may want to use a spudger to pry it up if it doesn't pull up easily.

Remove the speaker wires from the LCD screen.

Replace the LCD screen and solder the wires to the new screen.

This step requires soldering. Only do this step if you are OK with soldering small wires. Look at this guide for help with soldering.