Water spill on MacBook Pro, didn’t turn it off

Firstly you need to disconnect the battery this is key. although its switched of there is still power flowing through it. although there isn’t a guide specifically for this you can follow the teardown to step 6 which will show the battery disconnection process. if possible keep the screen separated from the keyboard or place a thing cloth between as when upside down water can leak into and behind the glass ruining your screen too.

Once disconnected if you are able to yourself you will want to fully tear down the machines as best you can and follow this guide . you will need to clean the boards with isopropyl alcohol. This will work best to try and clean up the corrosion from the water. although before you switched it off you only had an issue with your speaker corrosion will work overtime to render your laptop useless.