Uncover and remove the battery immediately. You can do this by removing the top two screws on the rear of the console
Remove the additional 10 screws to obtain access to the motherboard. Be cautious when removing the rear panel, there is a ribbon cable from camera attached to the motherboard. Unlatch the cable at the motherboard.
check for liquid damage inside the assembly. The ribbon cables for the digitizer screen are the bottom left and middle (when viewing from rear). check the connection.
Do not keep the system turned on or battery installed while there is liquid in the console. Remove using rubbing alcohol and pray it doesn't lead to corrosion. You may need to go deeper in the dis-assembly of the unit. Liquid may be sitting between the motherboard and LCD. I would check youtube for dis-assembly instructions.