There will be a manual somewhere but basically, you need a needle, a credit or debit card and a 1.5 Phillips screwdriver.
The needle is to poke and remove the tiny rubber plugs you always thought were to soften the lid closing. They actually cover the screws you need to remove with the Phillips driver.
The plastic card is to ease into the crack between the bezel and the lid. You then run that slowly and carefully all round until the bezel comes away.
More screws to undo to release the screen itself and take great care removing the sticky pad that protects and holds in the connector. My screen changes take twelve minutes on average but you should allow half an hour for the first time you do one.
Replacement is the reverse of the above except you squeeze the bezel back into its clips, but don't fit it all together until you've powered up and proved it works. Google is your best friends in finding tjhe manual.